Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions.

BACKGROUND: Pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) is a native pest of Asia and preferably invasion on cotton (Gossypium hirsutum L.) crop as a commendatory host plant. Commercially, G. hirsutum is known as white gold and is an important cash crop all over the globe. Limited studies were published to focus on certain dietary compositions against different cotton pests. Therefore, the present study was undertaken in the laboratory under controlled conditions (temperature: 27 ± 2°C and relative humidity: 60 ± 10%) to determine the impact of three different treatment diets (wheat germ meal, okra, and chickpea) on the biological aspects (lifetime, developmental period) of P. gossypiella.
RESULTS: Results revealed that the shortest larval time of P. gossypiella was observed on the okra feed diet while the longest period was recorded on the wheat germ diet. Meanwhile, the pupation delay was noted on the wheat germ diet. The dietary influence was also observed on adult stages of female and male P. gossypiella (43.00 and 37.50 days respectively) and compared with a standard diet (56.50 and 52.50 days respectively). Furthermore, larval weighed more on the okra and chickpea diet followed by the wheat germ diet, whereas highest pupal weight was observed on the standard diet followed by the chickpea diet and okra diet.
CONCLUSION: Developmental parameters were significantly variant across all treatment diets, whereas the higher significant difference was reported on the okra diet. Therefore, the existing data of this study offers fruitful interventions for the future as a modified diet for large-scale and rapid mass production of P. gossypiella larvae.

Background

Cotton, Gossypium hirsutum (L.) also known as white gold and is an important cash crop of Pakistan. Pakistan ranks as the 4th largest producer and 5th largest consumer of cotton in the world. Cotton is cultivated all over the globe with an estimated 32 million hectares for fiber, oil content, fuel, and employment needs [1]. Cotton contributed 0.8% to the gross domestic product (GDP) of Pakistan, whereas, yield decreased to 6% due to unfavorable weather conditions and severe attack of P. gossypiella that hampered cotton output (Pakistan Economic Survey 2019–20). Genus Gossypium belongs to the family Malvaceae recorded as a potential host for P. gossypiella [2]. Excluding cotton, alternative host plants of P. gossypiella over the globe can be categorized into 7 families, 24 genera, and 70 species. Among lepidopterans pests (bollworms) of cotton, pink bollworm (Lepidoptera: Gelechiidae) is a native pest of Asia and also prevalent in cotton cultivated areas of the world. It prefers cotton as a host plant to induce injury at its different growth stages [3].

P. gossypiella lay single white greenish eggs or a bunch of 15 or 20 eggs that change color before hatching [4]. Eggs hatch to neonate larva (2 mm) in 3–4 days with a yellowish and dark brown head, slowly attain a size of second instar (4 mm) having white color then turns to third instar (6 mm) possesses visible pink markings to appear against creamy to ivory background color [5]. Fully grown pink color fourth instar attain a size of 9 mm, feed inside the boll, then exit the boll by making a 2 mm cut and drops to the soil to pupate in case of the short cycle or go to diapause in case of the long cycle when days are short and temperature is falling. Bright brown pupae (7–10 mm long) remains immobile for 7–10 days, then matures into black pupae [6] which emerges into a small inconspicuous greyish moth (12-20mm) with dark spots on wings [5]. The female moth can lay up to 100–200 eggs after 2 days of the pre-oviposition period which can cause severe infestation at the early stage of cotton bolls that cause severe crop loss until quite late in the season. Pink bollworm larval period is 15–20 days and the life cycle is completed in 30–40 days. The principle to control it way is to monitor it at its close season and control the first instar stage that can prevent it from severe crop loss [7].

Many environmental, as well as laboratory-controlled factors [8], affect the developmental period of pink bollworm such as temperature at 29°C shorten incubation period of pink bollworm eggs, whereas coolest temperature [9] and longer exposure of reared larvae to 70°F temperature causes delayed pupation in them [10]. Both pupal period and total life span of pink bollworm vary with the type of food as shorter pupal and egg to emergence period of pink bollworm when fed as larvae on cotton squares compared to feed on cotton bolls [11]. Diet composition also affected the biology of pink bollworm as the higher fat content of the diet resulted in delayed pupation thus increase the incidence of diapause larvae [12-15]. Increased pupal weight increased larval period but reduced pupal weight. However, if the fat content of the diet is lower than the requirements would cause incomplete development of body features and also affect adult emergence [9]. The lower water content of the diet delayed pupation and increased diapause chances [16].

Mass rearing had intense effects on insect performance through first-hand rearing and so has a significant role in integrated pest management [17]. Commercial companies use mass-reared colonies of insects to evaluate pesticide effects, resistance in the host plant, production of replaced products of insect control include viruses, pheromones. The rearing of beneficial insects has great significance for growing industries to increase production and pest control. Many companies use reared insects as intercessors in medicinal products and agriculture [18]. Insect rearing technology involves producing a high number of quality strengthen laboratory insects that benefit entomology for different purposes [19]. As compared to rearing on natural food, rearing on artificial diet optimized to increased insect fitness, lessens the requirement of work effort, space, time, and expenses linked with the growth of host plants and also accessibility of artificial food helps in easier concur of insect growth [20].

The purpose of this study was to determine the impacts of different diet compositions on the developmental, larval and pupal weight of pink bollworms by separately rearing their larvae in reared cups to strictly avoid any contaminations.

Methods

Insect collections

For the pink bollworms egg collection, matured cotton bolls were collected from March to May from the cotton fields at The University of Agriculture, Faisalabad (UAF). The cotton bolls that possess diapause larvae (Fig 1) were transferred to glass cages in Pink Bollworm Rearing Laboratory, at the Department of Entomology, UAF under controlled laboratory conditions at 27 ± 2°C temperature and 70 ± 10% relative humidity (RH) that facilitated pupae development to adult emergence. Emerged adults in 1: 1 ratio of male to female was released in oviposition glass chimneys covered with towel tissue paper (white) as an egg lying substrate and provided with vial possessed adult diet (decavitamin drop: 1ml and 10% honey solution) for egg laying purpose. After 3 days of the preoviposition period, collected eggs from the ventral side (possessed grooves) of tissue paper followed shifting to plastic cups for egg hatching (Fig 2).

Fig 1

A-B: Pink bollworm moth collection cages. C: Infested cotton boll due to larval penetration of P. gossypiella. D: Larva feed inside the seed. E: Diapause larva under controlled laboratory condition.

Fig 2

A: Pink bollworm moth collection vial. B: Egg laying glass chimney covered with oviposition substrate (groves). C: Eggs laid in batches. D: Singly egg laid pattern in groves in towel tissue.

Starter culture

In maintained laboratory conditions, eggs hatched in 2–3 days. Before shifted neonate to rearing cups, noted eggs hatchability percentage because many damaged eggs (attacked by a predator or parasitoid) were not hatched that could further affect larval culture. Plastic cups containing neonate were exposed to torchlight that facilitated their transference to rearing cups (3.8x3.4x3cm) using a camel hair brush (Fig 3). Egg hatchability was checked daily to buildup larval culture for rearing purposes and transferred the hatched larvae to cups possessed diet for mass rearing of pink bollworm adults.

Fig 3

A: plastic cup possessed many neonates. B: Shifting of neonates using camel hair brush. C: Rearing cup possessed larvae from starter culture.

Experimental diets

Three treatment diets including standard diet (the wheat germ as the main ingredient), okra diet, and chickpea symbolized as T1, T2 and T3 were prepared differently according to their suggested formulations. Details of each diet composition are given in Tables 1 and 2. To avoid fungal contamination during diet preparation, firstly sterilized required equipment with 5% ethanol solution (25ml water) followed by autoclave were used. The standard diet prepared based on the technique suggested by [15] is given in Table 1. All ingredients were accurately weighed using electronic balance followed by three fractions (A, B, and C) of ingredients so a well mixed product can be obtained. Fraction A ingredients stirred well in 230 ml of distilled water in a 1000ml of measuring beaker. Then fraction B comprised of decavitamins (0.0l ml) was separately mixed in 10 ml of water in a measuring cylinder to make vitamin solution and then fraction C comprised of agar as a thickening agent was separately well stirred in 500ml of distilled water in a 1000ml of measure beaker followed by boiling it in the oven to make a uniform agar solution. After making fraction solutions, all fractions were blended step by step with the addition of 3.3 ml corn oil and 2 ml honey into a blender mixture followed by pouring of hot mixture into the Petri dishes (150mmx15mm) and allowed to solidify for 10 minutes. The solidified medium was cut with a spatula into small cubes (¼ inches) and placed in 3–4 diet cubes in a transparent plastic cup separately for the rearing of pink bollworm larvae.

Table 1

Wheat germ meal artificial diet and its gradients used in this study.

Components of Fraction A	Quantity (g.kg-1 or ml. L-1)	Components of Fraction B (Decavitamins: 0.01ml)	Quantity (mg.ml-1)
Wheat germ meal	34.5	Calcium pentothenate	0.12
Casein	30.0	Niacin	0.06
Sucrose	10.0	Riboflavin	0.03
Brewer’s yeast	5.0	Folic acid	0.03
Alpha-cellulose	1.0	Thiamine	0.015
Potassium sorbate	1.5	Pyridoxine hydrochloride	0.015
Nipalgin	0.5	Components of Fraction C	Quantity (g.kg-1 or ml. L-1)
Choline chloride	0.06	Agar-agar	20.0
Maize oil	3.3	Distilled Water	500ml
Honey	2.0
Distilled Water	230

Table 2

Ingredients of chickpea medium along with their quantity.

Components of Fraction A	Quantity (g. ml-1)
Chick pea flour	35
Sucrose	15
Distilled Water	200
Components of Fraction B
Agar-agar	19
Distilled Water	200
Components of Fraction C
Dried yeast powder	8.0
Ascorbic acid	1.2
Methyl 4-hydoxy benzoate	1.6
Multivitamin solution	1.0
Streptomycin sulphate	0.2
Bavistin	2.0
Casein	10
Cystiene	0.1
Wesson’s salt	2.5
Sorbic acid	0.5
Cholesterol	0.5

We collected fresh okra fruits (soft and fresh pods) from different fields of UAF then transfer them to pink bollworm rearing laboratory for pink bollworm larval diet. Firstly, we washed okra fruit with distilled water followed by drying then cut 15cm okra with cutter into 2.5 cm okra pieces and placed 5 okra pieces in each transparent plastic cup for larval rearing (Fig 4).

Fig 4

Rearing cups possessed okra diet pieces used for larval rearing.

Chickpea diet ingredients and preparation techniques were the same as developed by [21] and given in Table 2. Made three fractions of ingredients, labelled as A, B and C then mixed fraction A’s ingredients in 200ml of distilled water, warmed to 60°C with continuous stirred followed by cooling then added dissolved solution into a blender and mixed thoroughly. Then fraction B comprised of agar was boiled in 200 ml of distilled water in an oven followed by continued stirring until beading consistency was obtained, then blended dissolved viscous agar into fraction A. Finally, fraction C ingredients were added into fraction A mixture with continuous blending until a homogenous mixture was obtained. The prepared diet was poured into Petri dishes and diet cubes (2cm × 0.2cm × 0.5cm) were placed in rearing containers for larval rearing.

Experimental layout

The experiment was set up in a completely randomized design (CRD) comprised of three treatment diets including standard, okra, and chickpea diets and each treatment was replicated 10 times while possessed two larvae per replication.

Population rearing

After obtaining a successful culture of the neonate, there was a need to shift them on prepared diets for successful rearing. For rearing purposes, small-sized plastic cups with lids were used as reared containers to prevent larval escape, predator entry, diet contamination, and dehydration. Marked transparent plastic cups replicated 10 times for each treatment diet and using camel’s hair brush released freshly emerged neonates onto diet cubes at 2 larvae/cup and reared until pupation. For successful larval development, larvae shifted onto a fresh diet (Fig 5) for every third day while daily observed larval stage and increased diet according to the larval stage. The fourth stage larvae were sexed, weighed, and counted separately for adult pairing. Upon pupation, the pupae were weighed and transferred dark brown pupa in wide-mouthed specimen jars labelled as male and female for separate adult emergence and collection. After the pupation, the emerged adults were released in pairs into oviposition glass chimneys for mating and egg-laying purpose. Wide-mouthed round glass chimneys were used to prevent excessive flight activity, crowding of adults, preserve scales and facilitate mating among adults.

Fig 5

1: Neonate larva shifted on diet 2: Second instar larva feed on prepared diet 3: Third instar 4: Fully grown fourth instar ready to pre-pupate 5: Male and female dark brown pupae 6: Emerged pink bollworm adult.

Statistical analyses

Observations on biological parameters including incubation, larval, pupal, larval period and pupal weight, adult longevity and mean generation time were recorded for each larval diet and subjected to appropriate statistical analysis using statistical 8.1 software.

Results

Growth and development records of pink bollworm reared on three treatment diets are given in Table 3. Analysis of variance records indicates the instar duration of each larval stage significantly differed across three treatment diets. Instar period of newly hatched larvae was observed to be the shortest on the chickpea diet followed by the okra diet as compared to the standard diet, while [22] reported 2.34 ± 0.48 days for the first instar period on chickpea diet agreed with the present findings on chickpea diet. According to statistical analysis (Fig 6), the first instar period (2.4b) was noted to be significantly different on the chickpea diet as compared with the non-significant differences in the second instar period between standard and okra diet (3.6a and 3.4a).

Table 3

Growth and development of Pectinophora gossypiella reared on various treatment diets.

Diet	Biological Parameters (Days)
	1st Instar	2nd Instar	3rd Instar	4rth Male Instar	4rth Female Instar	Male Larval period	Female Larval period	Pupal period	Male life Cycle period	Female life Cycle period
Wheat germ meal	3.6a	4.7a	4.9a	6.2a	8.4a	19.4a	21.6a	8.6a	52.5a	21.0a
Okra	3.4a	3.5b	3.5b	3.7b	4.2b	14.0c	14.5b	7.7ab	39.8b	18.5a
Chickpea	2.4b	4.3ab	4.6a	6.2a	8.3a	17.5b	19.6a	7.3b	37.5b	12.1b
HSD value	0.5727	0.9710	0.7929	0.7784	0.7424	1.7457	2.1053	1.1414	3.7493	2.7614
F-Value	15.5**	4.87**	10.6**	42.3**	128**	30.3**	37.2**	4.19**	57.1**	29.4**

** Highly significance difference at 1% probability level; *Significance difference at 5% probability level; NS: no significant difference.

Means within a column shared by same letters are not significantly different at p>0.05 fallowed by Tukey’s test.

Fig 6

Larval instar’s duration (mean ±SE) of P. gossypiella on wheat germ, okra and chickpea diet.

The means followed by each instar’s bar gram by same letters are not significantly different at p>0.05 by Tukey’s HSD test.

The shortest second instar period was noted on the okra diet followed by larvae reared on chickpea diet as compared to the longest period recorded on wheat germ diet while the [15] findings (4.31 ± 0.76 days) slightly deviated from our results recorded on chickpea diet. According to statistical analysis, a significantly higher (4.7a), second instar period was recorded on the standard diet which was significantly different from the okra diet while there was no significant difference in the second instar period between okra (3.5b) and chickpea diet (3.5ab) or between the standard and the chickpea diet. The shortest third instar duration was observed on the okra diet followed by the chickpea diet as compared to the longest period noted on the wheat germ diet while the instar period on the okra diet was in agreement with the [22] results on chickpea diet. The statistical analysis described the third instar duration of P. gossypiella moth significantly higher (4.9a) on the standard diet but the instar period significantly differed (3.5b) when larvae reared on okra diet compared to those fed on the standard diet and chickpea diet (4.6a) that showed non-significant differences.

The third instar turned to dark pink color, the fourth instar distinct as male and female while both sexes showed different development duration depends on the type of diet on which both reared separately. The shortest period of male fourth instar was observed on okra diet followed by wheat germ diet and longest instar period was noted on chickpea diet which was in synchronism with [22] observations reported for male instar duration of 6.40 ± 0.52 days. Statistically analyzed, the fourth instar period of male larvae was significantly higher and did not significantly differ when fed on standard and chickpea diet (6.2a on both) as compared to okra diet (3.7b) on which significantly differed instar period was observed.

The observed shortest period of female fourth instar on okra diet followed by chickpea diet and longest instar period was noted on wheat germ diet while chickpea findings were in contrast with the [22] findings reported 5.60 ± 0.68 days female instar period on chickpea diet. Statistically analyzed, female fourth instar period was significantly higher on wheat germ diet (8.4a) and non-significantly differed from chickpea diet (8.3a) while significantly differed on okra diet (4.2b)

After the mean instar period was completed, the recorded total larval period as male and female were reared separate treatment diets. The shortest male and female larval was observed on okra diet followed by chickpea diet as compared to longest larval period on wheat germ diet while male larval period on chickpea diet was in line (Fig 7) with [22] findings (17.5 ± 1.95 days) and female larval period was in contrast with the [22] findings (8.15 ± 2.18 days). In present results, larval period recorded on chickpea diet was in conformation with [5] results recorded total larval period range from 18.26–18.96 days on seed powder of cotton cultivars and also in accord with the [23]) findings on hornworm diet. Okra diet findings were in contrast with the [24, 25] who reported the shortest instar period of 21.34 ± 2.61 days on two-phase diets (cottonseed flour and okra).

Fig 7

Larval period (mean ±SE) of male and female P. gossypiella on wheat germ, okra and chickpea diet.

The means followed by bar gram by same letters are not significantly different at p>0.05 by Tukey’s HSD test.

Present findings of the larval period on three different diets were in contrast with the earlier studies of [26] reported 11.33±0.64 days; [27] recorded 9 to14 days in the hotter region; Shah et al., 2013 noted 9 days at 35 ± 1°C and 13 days at 27 ± 1°C as well as [21] who found it to be 25.10 ± 0.994 days when reared on artificial medium. Larval period reported by [28, 29] was in agreement with the present findings. Statistical analyses indicate that the adult larval period differed highly significantly (P<0.01) when reared on selected larval diets. The present findings of the larval period were in contrast with earlier studies of [30] results reported the non-significant effect of cotton cultivars on pink bollworm larval period; [25] observed non-significant larval period difference across southern pink bollworm diet premix and cottonseed flour + Chickpea flour + okra diet but significant larval period difference noted by [25] on cottonseed flour, cottonseed flour + chickpea flour, cottonseed flour plus okra and southland multi-species diet premix that conformed with present findings.

Male larval period significantly differed across three treatment diets as lengthy male larval period observed when reared on the standard diet (19.4a) followed by reared on chickpea diet (17.5b) as compared to reared on the okra diet (14.0c). Female larval period significantly higher (21.6a) when larvae reared on the standard diet which differed non-significantly from larval period observed on the chickpea diet (19.6a) while significantly differed larval period (14.b) was observed on the okra diet. After the completion of larval development, the fourth instar larva of pink bollworm went to diapause state as it stopped feeding and moved slow, as a resulted in its body stretched and shield-like covering formed on body identified as the pre-pupal stage. The prepupal stage short that turns into the resting stage called the pupal stage in which developmental structures formed. The pupal period varied depending on the type of diet larvae reared.

As recorded from Table 4 the longest pupal duration recorded on the standard diet which was in agreement with [31] results reported 8 days pupal period at 35 ± 1°C and also slightly in accord with [32], findings reported 8.8 days on wheat germ diet. Pupal period recorded on standard diet was also in agreement with [28] findings on the cotton square, wheat germ, and modified wheat germ diet and in accord with the Bell and [33] findings on hornworm diet. Recorded shortest pupal period of larvae reared on chickpea diet which was in accordance with the [22] findings on chickpea die and more or less in agreement with [26] who found the pupal period consisting of 7.42 ± 0.20 days.

Table 4

Mean comparison of larval and pupal weights of pink bollworm reared on three treatment diets.

Diet	Larval weight	Pupal weight
	(mg)	(mg)
Wheat germ meal	17.6a	21.2a
Okra	19.6a	16.4b
Chickpea diet	19.4a	17.4b
HSD value	2.2700	1.9042
F-value	3.37NS	25.3**

**Significance difference at 1% probability level; *Significance difference at 5% probability level; NS: no significant difference.

Means within a column shared by same letters are not significantly different at p>0.05 fallowed by Tukey’s test.

Discussion

In contrast to present findings, Kandi (2016) recorded pupal period as 16.7 days at 25°C, [34] found 3.5 days pupal delayed at the varied temperature of 18 to 35°C, [25] reported the shortest pupal period of 7.96 ± 1.37 days when larvae reared on two-phase diets (cottonseed flour and okra), [21] recorded pupal period of 7.9± 0.88 days when reared on artificial medium, [30] noted pupal period ranging from 5.76–6.48 days when artificially reared larva on seed powder of cotton cultivars. According to statistical analysis, the pupal period of P. gossypiella differed significantly (P<0.05) across treatment diets. Similar to present results, the pupal period reported by [30] significantly differed on some cotton cultivars (G-27, Pusa 1752 and Gh-BHV-824) and the pupal period reported by [25] significantly differed on cottonseed + chickpea flour, cottonseed flour, southland multispecies diet premix.

Pupal period significantly higher (8.6a) and significantly differed when larvae reared on wheat germ diet than those reared on okra (7.7ab) and chickpea diet (7.3b) which show a non-significant difference in the pupal period. Similar to the present results, [25] found a significantly lengthen pupal period (8.78 ± 1.70c) on cottonseed flour + chickpea flour diet as compared to the non-significant shorter pupal period on other combinations of diets. The total life cycle period of pink bollworms depends on the type of diet on which larvae reared. According to the table, the longest life cycle period from egg to adult of female and male was recorded on the standard diet but only female total life span was in agreement while male life cycle period deviated from [22] findings who reported 56.30 ± 9.84 and 38.40 ± 4.48 days on chickpea diet. The developmental period of females and males on the okra die was in confirmation with [35] conclusions who reported mean generation time from egg to egg as 37.8 ± 3.8 days and is in agreement with [36, 37] findings. The total life span of female and male moth reared on chickpea diet was in accordance with reported results who noted female developmental period of 21 to 43 days. Present findings were contrary to earlier studies of [38] who described the total life cycle period of 25–30 days and [31] reported 30–32 days at 35 ± 1° C.

Statistical analysis (Fig 8) indicates that male and female life cycle periods differ highly significantly (P<0.01) on three treatment diets. Male life cycle period significantly higher (52.5a) when larvae reared on a standard diet and significantly differed from okra diet (39.8b) that non-significantly differed from chickpea diet (37.5b). Female life cycle period significantly higher (56.5a) on a standard diet and significantly differed from total life span observed on chickpea diet (43.9b) that non-significantly differed from okra diet (43.6b). Data from Table 3, larval weight observed highest on okra and chickpea diet followed by wheat germ diet. Pupal weight is an indicator of food conversion efficiency during larval stages, which was observed the highest on standard diet followed by chickpea diet and okra diet. Present findings on standard diet were in conformation with [39] results on processed cottonseed meal diets while the larval and pupal weight on okra and chickpea diet was in conformation with [21] findings who reported 21.40 ± 3.63 and 18.00 ± 2.73 mg weight. According to statistical analysis (Fig 9), larval weight was not different significantly (P>0.05) when reared on three treatment diets whereas significantly higher larval weight was observed when larvae fed on okra diet(19.6a) as compared to chickpea (19.4a) and standard diet (17.6a). While pupal weight differed significantly (P<0.05) across treatment diets which was inconsistent with the results recorded by [25] as pupal weight significantly differed on cottonseed flour + Okra, cottonseed flour + chickpea flour, and southland pink bollworm diet premix. Pupal weight was observed significantly higher (21.2a) and significantly differ on standard diet as compared to chickpea (17.4b) and okra diet (16.4b) that showed non-significant differences. Present results are in line with the [25] who recorded significantly highest pupal weight (21.78 ± 4.09a) on cotton.

Fig 8

Total life span (mean ±SE) of male and female P. gossypiella on wheat germ, okra and chickpea diet.

The means represent by bar gram by same letters are not significantly different at p>0.05 by Tukey’s HSD test.

Fig 9

Larval and pupal weight (mean ±SE) of P. gossypiella on wheat germ, okra and chickpea diet.

The means followed by bar gram by same letters are not significantly different at p>0.05 by Tukey’s HSD test.

Conclusion

The present study facilitates to develop an artificial diet for P. gossypiella prepared from locally available ingredients and a simple adaptable methodology by different researchers. Okra diet is useful for large-scale mass production of P. gossypiella due to rare contamination and easy handling whereas, in the case of other diets, contamination chances are high due to poor laboratory tools and mite infestation.

13 Jul 2021

PONE-D-21-18182

Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions

PLOS ONE

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Reviewer #1: Yes

Reviewer #2: Yes

**********

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Reviewer #1: Yes

Reviewer #2: Yes

**********

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Reviewer #1: Yes

Reviewer #2: Yes

**********

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Reviewer #2: Yes

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Reviewer #1: The article entitled "Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions" describes the diet impacts on biological parameters of destructive pest of cotton.The overall composition of the manuscript is good, is written in a clear and understanding manner with a very nice introduction to the topic. All used procedures are correct. The paper is scientifically and methodologically accurate, and the conclusions drawn are convincing. The linguistic style is sufficient for publication and the reference section is adequate. This manuscript will find the interest of many readers and researcher of entomology. However, there are few gaps still remains. In my opinion, these gaps must remove before publications.

The manuscript can be accepted after the following issues are addressed.

Minor comments:

Introduction

Line 17, suggested to write as There are limited studies were published to focused

Line 20, replace influence to impacts

Line 31, write as parameters were significantly varient across all treatment

Line 33, must removed some insights into

Line39, correct grammar and sentences

Line 40, write as, more than 100 countries with an estimated

Line 41, replace percent with % an same as in the Line 42

Line 43, write technical name of pink bollworm and whole manuscript as well

Line 46, correct sentence

Line 50, suggested to write white greenish eggs or bunch of 15 or 20 eggs that changes the color

Reference in text section should be changes with latest reference

Line 91-93, suggested to write The purpose of this study was to determine the impacts of different diet composition on developmental, larval and pupal weight of pink bollworm by separately rearing their larvae in reared cups to strictly avoid to any contaminations

Line 96, Write Insect collections

Line 136, remove space

Line 140. Write as and given in table 2

Line 147, remove space

Line 168, remove repetitions

Line 180, remove space

Lin 200-2001, remove space

In the discussion section must include latest reference

Line 307, replace facilitate

The sequence, heading, sub heading of manuscript should be according to journal requirements

Reviewer #2: Reviewer comments

Article title: Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions

Editor in Chief

Thank you for providing me with an opportunity to review the article for your prestigious journal, PLOS One. I have reviewed the article and here are my comments/suggestion for the authors.

Comments for authors

Abstract

1. Line # 15. “Asia and preferably invade cotton crop, Gossypium hirsutum (L.)”, rephrase as “Asia and preferably invade cotton (Gossypium hirsutum L.) crop.

2. Line # 16. put comma after commercially.

3. Line # 18-19. G. hirsutum rearing ------------ conditions, rearing what? Make correction.

4. There are few grammatical and punctuation mistakes author need to carefully revise this section.

5. Introduction/Background

1. Cotton, Gossypium hirsutum (L.) change this to Cotton (Gossypium hirsutum L.)

2. Line # 38 & 40. Cotton is grown in more ----- employment needs, make this sentence grammatically correct.

3. Line # 51-59, require substantial rephrasing, the sentence/s are too long, and contain grammatical errors. Further, too many outdated citations.

4. There are several overlapping information in this section, authors are advised to remove such information.

5. Remove all outdated references and keep the latest.

Material and Methods

Authors described very detailed MM section.

Results

1. Results are described without heading, make sub-headings and describe information under those sub-headings.

Discussion

1. The discussion need to revised make it more focused based on results.

2. Remove the overlapping information/statements.

References

1. Update the reference section with latest findings keep only those old reference which are utmost important.

Comments for Editor

1. Article can be accepted after suggested modifications.

**********

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Reviewer #1: No

Reviewer #2: No

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11 Sep 2021

Dated. 2021-08-24

Professor Dr. Adnan Noor Shah

PLOS ONE

Dear Subject Editor,

Subject: Resubmission of our revised manuscript titled “Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions (PONE-D-21-18182).

With this cover letter, we would like to resubmit the revised manuscript (PONE-D-21-18182) for the publication in PLOS ONE. We would also like to thank the editors and reviewers for the careful and constructive reviews and we honestly feel that reviewer’s insightful suggestions helped us to improve the manuscript profoundly. All the revisions can be easily identified from highlights made in the revised manuscript. Once again thanks for your co-operation and valuable comments and suggestion.

We submitted the revised manuscript file with all suggested corrections highlighted green in the main file. Furthermore, Reviewer comments was addressed point-by-point with reference to revised page and line numbers in the rebuttal letter and main file.

Kind regards.

Dr. Habib Ali

Khwaja Fareed University of Engineering and Information Technology, Rahim Yar Khan, Pakistan Telephone number: +923106084708; Email: habib_ali1417@yahoo.com

Based on the comments of the reviewers, we have made changes to the manuscript and highlighted them in green for reviewer whose details are mentioned bellow:

Respond to the evaluation as suggested by the Editors & reviewers

Response to Reviewer # 1:

Dear reviewer, we are grateful to you for your comments and suggestions for the improvement of the article. We have tried our best to revise the manuscript in light of your comments.

Reviewer #1:

The article entitled "Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions" describes the diet impacts on biological parameters of destructive pest of cotton.The overall composition of the manuscript is good, is written in a clear and understanding manner with a very nice introduction to the topic. All used procedures are correct. The paper is scientifically and methodologically accurate, and the conclusions drawn are convincing. The linguistic style is sufficient for publication and the reference section is adequate. This manuscript will find the interest of many readers and researcher of entomology. However, there are few gaps still remains. In my opinion, these gaps must remove before publications.

The manuscript can be accepted after the following issues are addressed.

Minor comments:

Introduction

Line 17, suggested to write as There are limited studies were published to focused

Rebuttal: Correction has been made (Line number 43)

Line 20, replace influence to impacts

Rebuttal: Correction has been made (Line number 46)

Line 31, write as parameters were significantly varient across all treatment

Rebuttal: Correction has been made (Line number 57)

Line 33, must removed some insights into

Rebuttal: Correction has been made (Line number 58)

Line39, correct grammar and sentences

Rebuttal: Correction has been made (Line number 65)

Line 40, write as, more than 100 countries with an estimated

Rebuttal: Correction has been made (Line number 66)

Line 41, replace percent with % an same as in the Line 42

Rebuttal: Correction has been made (Line number 67-68)

Line 43, write technical name of pink bollworm and whole manuscript as well

Rebuttal: Correction has been made (Line number 69-71)

Line 46, correct sentence

Rebuttal: Correction has been made (Line number 76)

Line 50, suggested to write white greenish eggs or bunch of 15 or 20 eggs that changes the color

Rebuttal: Correction has been made (Line number 76)

Reference in text section should be changes with latest reference

Rebuttal: Correction has been made in the whole manuscript

Line 91-93, suggested to write The purpose of this study was to determine the impacts of different diet composition on developmental, larval and pupal weight of pink bollworm by separately rearing their larvae in reared cups to strictly avoid to any contaminations

Rebuttal: Correction has been made (Line number 117-119)

Line 96, Write Insect collections

Rebuttal: Correction has been made (Line number 122)

Line 136, remove space

Rebuttal: Correction has been made (Line number 124)

Line 140. Write as and given in table 2

Rebuttal: Correction has been made (Line number 166)

Line 147, remove space

Rebuttal: Correction has been made (Line number 175)

Line 168, remove repetitions

Rebuttal: Correction has been made (Line number 191)

Line 180, remove space

Rebuttal: Correction has been made (Line number 197)

Lin 200-2001, remove space

Rebuttal: Correction has been made (Line number 221)

In the discussion section must include latest reference

Rebuttal: Correction has been made

Line 307, replace facilitate

Rebuttal: Correction has been made (Line number 192)

The sequence, heading, sub heading of manuscript should be according to journal requirements

Rebuttal: Correction has been made according to the journal requirement

Response to Reviewer # 2

Article title: Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions

Editor in Chief

Thank you for providing me with an opportunity to review the article for your prestigious journal, PLOS One. I have reviewed the article and here are my comments/suggestion for the authors.

Rebuttal: Dear reviewer, we are grateful to you for your comments and suggestions for the improvement of the article. We have tried our best to revise the manuscript in light of your comments.

Comments for authors

Abstract

1. The manuscript can be accepted after the following issues are addressed.

Minor comments:

Line # 15. “Asia and preferably invade cotton crop, Gossypium hirsutum (L.)”, rephrase as “Asia and preferably invade cotton (Gossypium hirsutum L.) crop.

Rebuttal: Correction has been made (Line number 41)

2. Line # 16. put comma after commercially.

Rebuttal: Correction has been made (Line number 42)

3. Line # 18-19. G. hirsutum rearing ------------ conditions, rearing what? Make correction.

Rebuttal: Correction has been made (Line number 45)

4. There are few grammatical and punctuation mistakes author need to carefully revise this section.

Rebuttal: All grammatical error and mistakes has been removed in the whole manuscript

5. Introduction/Background

1. Cotton, Gossypium hirsutum (L.) change this to Cotton (Gossypium hirsutum L.)

Rebuttal: Correction has been made

2. Line # 38 & 40. Cotton is grown in more ----- employment needs, make this sentence grammatically correct.

Rebuttal: Correction has been made (Line number 66)

3. Line # 51-59, require substantial rephrasing, the sentence/s are too long, and contain grammatical errors. Further, too many outdated citations.

Rebuttal: Correction has been made (Line number 78)

4. There are several overlapping information in this section, authors are advised to remove such information.

Rebuttal: All overlapped material has been removed

5. Remove all outdated references and keep the latest.

Rebuttal: latest reference has been added in the whole manuscript

Material and Methods

Authors described very detailed MM section.

Rebuttal: Detailed information has been added in the MM section

Results

1. Results are described without heading, make sub-headings and describe information under those sub-headings.

Rebuttal: Heading, sub heading has been added in the Result section

Discussion

1. The discussion need to revised make it more focused based on results.

Rebuttal: Discussion has been revised according to the requirement

2. Remove the overlapping information/statements.

Rebuttal: All overlapped material has been removed in the whole manuscript

References

1. Update the reference section with latest findings keep only those old reference which are utmost important.

Rebuttal: latest reference has been added in the whole manuscript

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

28 Sep 2021

Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions

PONE-D-21-18182R1

Dear Dr. Ali,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Adnan Noor Shah, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

28 Oct 2021

PONE-D-21-18182R1

Diet impacts on the biological aspects of pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae) under controlled laboratory conditions

Dear Dr. Ali:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Adnan Noor Shah

Academic Editor

PLOS ONE