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ThesisItem Unknown STUDIES ON THE IMPACT OF IPM AND NON-IPM PRACTICES ON OKRA PESTS, NATURAL ENEMIES AND PESTICIDE RESIDUES(COLLEGE OF HORTICULTURE VENKATARAMANNAGUDEM- 534 101, WEST GODAVARI DISTRICT, 2019-08-05) PUVVALA VISWANADHA RAGHUTEJA; Dr. N. EMMANUELThe present investigations on “Studies on the impact of IPM and non IPM practices on okra (Abelmoschus esculentus L.) pests, natural enemies and pesticide residues” was carried out during rabi 2018-19 at College of Horticulture, Venkataramannagudem, West Godavari district, A.P, with an objective of examining the influence of IPM and non-IPM practices on pest complex as well as on natural enemies, yield and yield attributes on okra. Further, the study was also undertaken to estimate the pesticide residue levels in okra fruits from non-IPM plots. IPM practices adopted were deep ploughing, growing maize as border crop, reflective plastic mulch, marigold as trap crop, installation of yellow sticky traps, light traps and sex pheromone traps, erection of bird perches, need based application of botanicals and bioagents; and in non IPM okra plot selected insecticides were sprayed on sequential basis. The mean population of jassids (A. devastans devastans) was 2.82 ± 0.39 number per okra leaf in IPM plot, whereas in the non-IPM plot the jassid population was 5.43 ± 1.20 number per leaf and in control plot it was 8.46 ± 2.77 number per leaf. The overall mean population of whiteflies (B. tabaci) was 0.42 + 0.08 number per leaf in IPM plot of okra, while it was 1.17 ± 0.22 number and 4.54 ± 2.24 number per leaf in non-IPM and control plots respectively. The average population of aphid (A. gossypii) in IPM plot of okra was 0.27 ± 0.11 number per leaf, whereas in non-IPM plot it was 1.11 ± 0.40 number and in control plot, it was 2.79 ± 1.23 number per leaf. The average population of two spotted mites (T. utricae) per sq.cm leaf area was found 0.54 ± 0.28 number in IPM plot of okra, whereas it was 1.03 ± 0.41 number and 4.04 ± 2.71 number per sq.cm per leaf area in non-IPM and control plots of okra, respectively. The mean number of E. vittella larvae was 0.43 ± 0.16 and 0.61 ± 0.15 number per fruit in okra grown in IPM and non-IPM plots respectively, while in control plot of okra the number of E. vittella larvae was 1.64 ± 0.14 no. per fruit. Similarly, the bud infestation was lowest in the buds of IPM plot with 3.06 ± 0.91 per cent bored holes. However, it was 6.22 ± 2.06 per cent in non-IPM plot, while in control plot it was maximum of 21.24 ± 3.76 per cent. The results further revealed that the mean population of natural enemies viz., spiders and coccinellid beetles were found 3.58+ 2.39 number per plant in IPM as compared to 2.70+ 2.39 number per plant in non-IPM plot, while in the control plot of okra the mean number of natural enemies recorded were 3.22+ 2.48 number per plant. The influence of IPM and non-IPM practices were studied on yield and yield attributes of okra viz., total fruit yield, infested fruit yield, marketable fruit yield and benefit cost ratio. The total fruit yield recorded was 64.35 + 2.59 kg in okra grown in IPM plot, while in non-IPM plot the fruit yield was 57.63 + 1.69 kg, whereas the lowest fruit yield of 46.87 + 1.43 kg was recorded in control plot of okra. The mean marketable fruit yield was 60.42 + 2.53 kg in IPM plot of okra which was more than that of non-IPM and control plots of okra with mean marketable fruit yield of 46.67 + 1.49 kg and 25.01 + 1.26 kg, respectively as the mean infested fruit yield was maximum in control plots in comparison to that of IPM plots. The observations on benefit cost ratio of okra plots showed that the highest benefit cost ratio was recorded in IPM plot with 2.11, whereas in non IPM plot of okra it was 1.23 and the lowest benefit cost ratio of 0.95 was recorded in control plot of okra. Levels of pesticide residues in the okra fruits obtained from IPM, non IPM and local tadepalligudem market was estimated at Pesticide Residue and Food Quality Analysis Laboratory (PRFQAL), University of Agricultural Sciences, Raichur, Karnataka. The residues of imidachloprid (6.7 ppm), thiomethoxam (3.8 ppm), flubendiamide (7.9 ppm), chlorantraniliprole (6.5 ppm) were identified in the harvested okra fruits from non-IPM plot which are far above the maximum residue limits (MRL), however no pesticides were detected in the okra fruits from IPM plot. Further, a sample of okra fruits were collected from tadepalligudem market and analyzed for multiresidues. Surprisingly, out of 74 chemicals tested, profenophos with 0.048 ppm was detected which was above the MRL of 0.01 ppm.ThesisItem Unknown STUDIES ON PLANT CHARACTERS OF PALM HOSTS (COCONUT AND OIL PALM) RELATING TO RUGOSE SPIRALLING WHITEFLY, Aleurodicus rugioperculatus MARTIN INCIDENCE - CONVENTIONAL CONTROL MEASURES(College of Horticulture, Venkataramannagudem, Dr.Y.S.R. Horticultural University, 2019-08-04) SINGAM SUSHMITHA; Dr. A. SUJATHAThe investigation entitled “Studies on plant characters of palm hosts (coconut and oil palm) relating to Rugose Spiralling Whitefly, Aleurodicus rugioperculatus Martin incidence – conventional control measures” was carried out during 2018-19 at Dr. Y.S.R.HU, Venkataramannagudem, Andhra pradesh to know the diagnostic symptoms, nature and extent of the damage, host range and occurrence of natural enemies of RSW in infested gardens. Influence of leaf bio physical and chemical characters on RSW intensity was estimated through laboratory studies. Field experiments were also conducted to evaluate the effective color and height of the sticky trap for managing the RSW population. The presence of egg spirals on the underside of leaves, heavy white waxy material, sticky honeydew around the infested area, black sooty mold formation were recorded as typical symptoms of RSW. Nymphs and adults of RSW were found to cause the damage by congregating heavily on the abaxial surface of leaves and sucking sap from host plants leading to loss of vitality of the plant. The RSW infestation, incidence and damage intensity was highest on oil palm crop but the population count/leaf was highest on guava crop. The pest status was high and occurring on more number of crops in West Godavari district when compared to that of East Godavari district of A.P. However on cocoa crop, least counts were recorded on all aspects evidencing that cocoa was least preferred crop while, oil palm being highly preferred crop for RSW, which was laden with RSW population. Occurrence of natural enemies of RSW viz., predators like coccinellids and spiders were recorded on coconut, oil palm and guava crops. Leaf biophysical characters viz., the length and width were significantly correlated with RSW infestation in coconut, oil palm and guava crops whereas thickness was negatively significantly correlated. Among the leaf biochemical characters; moisture, chlorophyll, proteins and total sugars content were found positively significantly correlated with RSW infestation but phenols were negatively significantly correlated. While fiber and lignin contents were found positively non significantly correlated with the RSW infestation. Yellow and green sticky traps were found more effective in attracting RSW adults and counts were significantly on par with each other in coconut crop whereas in guava crop, yellow sticky trap attracted significantly highest number of RSW adults. With weather parameters viz., minimum and maximum temperatures, the populations of RSW was positively and highly significantly correlated whereas, natural enemies were negatively and highly significantly correlated. The rainfall and RH were non significantly positively and negatively correlated with RSW population in coconut garden, respectively while in guava the RSW population was negatively and positively correlated with rain fall and RH, respectively. The natural enemies population were non-significantly positively correlated with rainfall and RH. The population of RSW was highly significantly and negatively correlated with populations of spiders and coccinellids in coconut and guava gardens indicating that, the increased population of coccinellids and spiders results in decreased RSW population.ThesisItem Unknown INVESTIGATIONS ON BIODIVERSITY OF BORER COMPLEX AND NATURAL ENEMIES ON SAPOTA (Manilkara achras) IN ANDHRA PRADESH(COLLEGE OF HORTICULTURE DR. Y.S.R. HORTICULTURAL UNIVERSITY VENKATARAMANNAGUDEM, WEST GODAVARI (Dist.) – 534 101, 2018-10-15) R. S. KARTHIK; Dr. A. SUJATHAThe present studies on “Investigations on biodiversity of borer complex and natural enemies on sapota (Manilkara achras) in Andhra Pradesh” was carried out during 2017-18 at HRS, Venkataramannagudem and two sapota orchards maintained by farmers at Kothapalli Village in West Godavari District and Mannetikota village in Prakasam district. The studies were conducted to know the diagnostic symptoms, nature of damage and extent of the damage by different borer pests, occurrence of natural enemies on the sapota pests and varietal evaluation of twelve sapota varieties viz., PKM-1, PKM-2, PKM-3, CO-1, CO-2, Kalipatti, Cricket Ball, Singapore, DHS-1, DHS-2, Pala and Kirthibarthi. The presence of hole on the buds and fruits of sapota and webbing of shoots were recorded as typical symptoms of borer pests. The borer pests attacked the leaves, buds and fruits of sapota damaging internal contents by boring, ultimately leading to yield loss. The study revealed that the bud borer, chiku moth, fruit borer and seed borer pests were causing serious losses in Mannetikota village of Prakasam district whereas bud borer, chiku moth and seed borer were serious in West Godavari district. The total life cycle of bud borer was 28.35 ± 1.18 days. The bud borer and chiku moth incidence was at lower levels during the second and first fortnight of October, respectively whereas, seed borer incidence was at lower level during second fortnight of November. Among the twelve varieties studied, the least preferred variety for borer damage was ‘Singapore’ hence it can be recommended for area expansion of sapota crop in coastal Andhra Pradesh. Biophysical factors viz., seed number was non-significantly positively correlated with seed borer damage and smooth surface textured fruit varieties were damaged more by seed borer, compared to rough surface texture whereas no correlation was found between fruit shape and fruit flesh texture with seed borer damage. The bud biochemical character, bud titratable acidity was non-significantly negatively correlated with bud borer damage, whereas it was non-significantly positively correlated with chiku moth damage. The moisture content of buds of sapota varieties was non-significantly negatively correlated with both bud borer and chiku moth damage. The fruit bio-chemical characters viz., TSS, total sugars, TSS acid ratio and reducing sugars content in sapota fruits were, non-significantly positively correlated with seed borer damage, except the characters titratable and non reducing sugars content which were non-significantly negatively correlated with the seed borer damage.ThesisItem Unknown SCREENING OF VARIETIES AND EVALUATION OF BIOPESTICIDES AGAINST SPOTTED POD BORER, Maruca vitrata (Geyer) on INDIAN BEAN (Lablab purpureus var. typicus)(COLLEGE OF HORTICULTURE DR. Y.S.R. HORTICULTURAL UNIVERSITY VENKATARAMANNAGUDEM, WEST GODAVARI (Dist.) – 534 101, 2018-07-28) V. DIVYA BHARATHI; Dr. C. P. VIJIStudies on “SCREENING OF VARIETIES AND EVALUATION OF BIOPESTICIDES AGAINST SPOTTED POD BORER, Maruca vitrata (Geyer) on INDIAN BEAN (Lablab purpureus var. typicus)” was carried out during Kharif, 2017-18 at College of Horticulture, Venkataramannagudem, Dr.Y.S.R. Horticultural University, West Godavari District. Nine determinate Indian bean varieties viz., Arka Amogh, Arka Jay, Arka Sambharam, Arka Soumya, Arka Vijay, NIB-1, Konkan Bhushan, Tirupathi Local and West Godavari Local were screened to know the infestation of spotted pod borer, M. vitrata. The overall mean larval population per plant was recorded least in variety NIB-1. The incidence of larval population was highest during 44 SMW when the crop was in full flowering stage. Regarding biophysical characters which contributed to resistance, morphological characters of flower viz., flower colour, number of flowers per plant, length of the flower shoot, number of flowers per shoot, average distance between two nodes, number of flowers per node, days required for flower initiation, number of infested flowers per plant were nonsignificant with per cent flower damage. Morphological characters of pod like, pod wall thickness (0.852), pod length (0.756), pod weight (0.709), number of seeds per pod (0.795), seed length (0.850), seed width (0.798), seed weight (0.828) were significantly positively correlated with per cent pod damage due to spotted pod borer, M. vitrata. Biochemical characters of flowers viz., moisture content (0.988), reducing sugars (0.995), non-reducing sugars (0.937), total sugars (0.990) and total protein content (0.928) were significantly positively correlated with per cent flower damage whereas, chlorophyll content (-0.691), phenols (-0.824), fibre content (-0.860) in flowers were significantly negatively correlated with per cent flower damage. Biochemical characters of pods viz., moisture content (0.878), reducing sugars (0.900), non-reducing sugars (0.875), total sugars (0.943), total protein content (0.971) and Name of the Author : V. DIVYA BHARATHI Title of the Thesis : SCREENING OF VARIETIES AND EVALUATION OF BIOPESTICIDES AGAINST SPOTTED POD BORER, Maruca vitrata (Geyer) on INDIAN BEAN (Lablab purpureus var. typicus) Submitted for the Award of : Master of Science in HORTICULTURE Department : HORTICULTURAL ENTOMOLOGY Faculty : HORTICULTURAL ENTOMOLOGY Major Advisor : Dr. C.P. VIJI University : Dr. Y.S.R. HORTICULTURAL UNIVERSITY chlorophyll content (0.736) were significantly positively correlated with per cent pod damage whereas, phenols (-0.923), fibre content (-0.985) in pods were significantly negatively correlated with per cent pod damage. Based on flower infestation per cent, NIB-1 (17.75 %) was categorised as highly resistant. Tirupathi Local (33.00 %) as moderately resistant and varieties Arka Soumya, Arka Vijay, Arka Amogh, Arka Sambhram, West Godavari Local, Arka Jay and Konkan Bushan were rated as intermediate resistant to M. vitrata which recorded flower infestation level at 52.60 51.94, 50.21, 47.25, 42.64, 42.2 and 41.45 per cent, respectively. Based on per cent pod infestation per cent, NIB-1was found to be tolerant (20.00 %). Varieties Arka Vijay, Arka Amogh, Tirupathi Local, Konkan Bhushan and Arka Soumya registered the pod infestation of 24.60, 25.30, 32.10, 36.30 and 37.70 per cent, respectively were graded as moderately susceptible. Varieties Arka Sambhram (43.60 %), Arka Jay (44.90 %) and West Godavari Local (50.00 %) were categorized as highly susceptible. The yield of varieties Tirupathi Local, Konkan Bhushan, Arka Amogh, Arka Jay, West Godavari Local, Arka Vijay, Arka Sambhram, Arka Soumya and NIB-1 was 8.11, 7.29, 6.83, 5.87, 4.83, 4.71, 4.66, 4.46 and 3.79 tonnes/ha, respectively. Eight biopesticides viz., NSKE, Neem oil, Pongamia oil, Bacillus thuringiensis var. kurstaki, Beauveria bassiana, Metarrhizium anisopliae, Lecanicillium lecanii were field evaluated to know the efficacy against spotted pod borer, M. vitrata in variety Arka Jay. The mean per cent reduction in larval population over control in order of B. t. var. kurstaki (59.14 %) ˃ NSKE (50.00 %) ˃ M. anisopliae (47.64 %) ˃ B.bassiana (42.17 %) ˃ neem oil (39.60 %) ˃ pongamia oil (32.72%)˃ L. lecanii (26.97%). The per cent reduction of flower infestation in the order of B. t. var. kurstaki (27.70 %) ˃ NSKE (21.24 %) ˃ M. anisopliae (20.00 %) ˃ B.bassiana (17.86 %)˃ neem oil (15.19 %) ˃ pongamia oil (11.15 %)˃ L. lecanii (4.58 %). The per cent reduction of pod infestation in the order of B. t. var. kurstaki (67.64 %) ˃ NSKE (61.99 %) ˃ M. anisopliae (54.55 %) ˃ B. bassiana (45.31 %) ˃ neem oil (39.22 %) ˃ pongamia oil (31.83 %) ˃ L. lecanii (28.42 %). Highest yield was recorded in treatment B. t. var. kurstaki (7.86 t/ha) followed by NSKE (7.20 t/ha), M. anisopliae (6.80 t/ha), B. bassiana (6.22 t/ha), neem oil (5.96 t/ha), pongamia oil (5.38 t/ha) and L. lecanii (4.98 t/ha).ThesisItem Unknown INQUEST ON PEST INCIDENCE AND SCREENING OF POTATO (Solanum tuberosum L.) VARIETIES AGAINST MAJOR PESTS IN GODAVARI DISTRICTS OF ANDHRA PRADESH(COLLEGE OF HORTICULTURE VENKATARAMANNAGUDEM, WEST GODAVARI (Dist.) – 534 101, 2018-07-28) POREDDY DAMODAR REDDY; Dr. A. SUJATAThe present investigation on “Inquest on pest incidence and screening of potato (Solanum tuberosum l.) varieties against major pests in Godavari Districts of Andhra Pradesh” was carried out during Rabi, 2017-18 in two locations 1. College of Horticulture, Venkataramannagudem, West Godavari District 2. Horticultural Research Station, Pandirimamidi, West Godavari District. The objective of the study was to study the incidence and to screen various potato varieties in order to identify resistant sources against major pests of potato and further authenticate their biophysical and biochemical basis of resistance against major pests of potato. In the present investigation, the occurrence of sucking pests viz.,whitefly, (Bemisia tabaci), leaf hopper, (Amrasca biguttulabiguttula) was commenced from 41st SMW and reached its peak at 45 th SMW, the foliage feeding pests viz., tobacco caterpillar and epilachna beetle (Henosepilachna vigintioctopunctata) was commenced from 42nd SMW and attains its peak during the 45th SMW at COH,Venkataramannagudem. In HRS, Pandirimamidi the incidence of sucking and foliage feeding pests were commenced from 42 nd SMW and attains its peak activity during the 44th SMW. Among eight of potato tested, none of them were immune to insect pests incidence. In College of Horticulture, Venkataramannagudem, the lowest incidence of foliage sucking and foliage feeding insect pests was recorded in potato variety Kufri Badshah (T5 ) followed by Kufri Surya (T1) and the highest incidence was recorded in the treatment Kufri Khyati (T2), followed by Kufri Phukraj (T6). In Horticultural Research Station, Pandirimamidi the lowest incidence of foliage sucking and foliage feeding insect pests were recorded in the treatment Kufri Himalini (T8) followed byT5- Kufri Badshah, the highest incidence was recorded in Kufri Jyoti (T7) followed by Kufri Chipsona-3 (T3). Among eight varieties of potato tested, at College of Horticulture, Venkataramannagudem, potato variety Kufri Badshah (T5) was resistant against insect pests with lowest number of insect pests per plant, while Kufri Khyati (T2) was susceptible against insect pests with highest number of insect pests per plant. At Horticultural Research Station, Pandirimamidi, the variety Kufri Himalini (T8) was showed the resistance against insect pests with lowest number of insect pests per plant, while Kufri Jyoti (T7) was susceptible against insect pests with highest number of insect pests per plant. Among the biophysical (quantitative) characters studied, the parameter trichome density showed the significantly negative correlation with the pest population per plant, the remaining biophysical (quantitative) parameters viz., plant height, intermodal length, number of leaves, were non significantly negatively correlated with the pest population per plant. Among the biochemical (qualitative) characters studied, the parameter phenol content in leaves showed the significantly negatively correlation with the pest population per plant, the remaining biophysical (quantitative) parameters viz., sugar content, protein content, moisture content were significantly positively correlated with the pest population per plant.ThesisItem Unknown TOXICOLOGICAL AND BIOCHEMICAL EFFECTS OF INDIGENOUS PLANT EXTRACTS AGAINST DIAMONDBACK MOTH (Plutella xylostella Linn.)(COLLEGE OF HORTICULTURE, Dr. Y. S. R. HORTICULTURAL UNIVERSITY VENKATARAMANNAGUDEM, WEST GODAVARI – 534 101, 2018-07-27) MANEM NAGA MOUNIKA; Dr. N. EMMANUELThe present investigation on “Toxicological and biochemical effects of indigenous plant extracts against diamond backmoth (Plutella xylostella L.)” was carried out at College of Horticulture, Venkataramannagudem, Dr.Y.S.R. Horticultural University, West Godavari District during 2017-18.The objective of the study was to evaluate antifeedancy, toxicity and normal adult emergence inhibition of plant extracts against P. xylostella and their biosafety against B. hebetor. Out of 10 indigenous plant extracts tested for anifeedancy against P. xylostella larvae the methanol extract of, A. calamus (AI50 =0.019%) was found to be supirior than A. indica (AI50 =0.021%) in causing antifeedancy. Amongst the hexane extracts evaluated for their antifeedancy, A. calamus (AI50 = 0.022%) was superior in causing 50.00 per cent antifeedancy, followed by A. indica (AI50 = 0.027%) and A. squamosa (AI50 = 0.050%). Among the aqueous extracts A. calamus (0.030%) is at par with A. indica (0.029%) in causing 50.00 per cent antifeedancy, followed by A. squamosa (0.058%), while S. nuxvomica (0.069%), C. citratus (0.070%), and V. negundo (0.070%) are at par with each other in causing the same effect. On the basis of AI50 values, hexane and methanol extracts of A. calamus rhizomes when applied on the leaf disc showed 1.246 and 1.072 times better antifeedant activity than the neem, whereas the aqueous extract A. calamus is 0.983 times less effective than A. indica in causing the same effect. However, the hexane, methanol and aqueous extracts of leaves and seeds of various plants were inferior to A. indica extract in causing 50.00 per cent antifeedancy On the basis of LC50 values, A. calamus (LC50 = 0.019%) methanol extract was highly toxic to P. xylostella larvae than other plant extracts viz., A. indica (LC50 = 0.020%) and V. negundo (0.027%), S. nuxvomica (0.054%), C. collinus (0.057%) and A. squamosa (0.213%). Based on LC50 values, the methanol extract of A. calamus rhizomes was found to be 1.060 times more effective than A. indica extracts in causing 50.00 per cent mortality of P. xylostella larvae. Out of all the aqueous extracts lowest LC50 value was recorded for A. indica (LC50 = 0.028%), followed by A. calamus (LC50 = 0.033%), and V. negundo (LC50 = 0.057%) in causing 50.00 per cent larval mortality. Out of all the plant extracts tested for normal adult emergence inhibition of P. xylostella larvae the methanol extracts of A. indica (I50 = 0.018 %) was more effective in causing 50.00 per cent normal adult mergence inhibition, followed by A. calamus (I50 = 0.025%) and V. negundo (I50 = 0.032%). However, the hexane extracts of A. indica (I50 = 0.023%) and A. calamus (I50 = 0.026%) are at par, followed by V. negundo (I50 = 0.052%). None of the plant extracts tested are more effective than A. indica in causing normal adult emergence inhibition. The total protein content of P. xylostella larvae haemolymph content was significantly reduced irrespective of the extracts when compared to untreated control. Methanol extract of A. calamus rhizome extract was reported to cause maximum reduction in total protein content in the haemolymph to the tune of 32.30 mg/ml at 5.0 % concentration which is statistically at par with A. indica methanol extract (32.60 mg/g) as against 38.76 mg/g in control. The hexane and aqueous extracts of all the plant extracts though showed drastic reduction in comparison with the controls but were not significant when compared to methanol extracts. P. xylostella larvae when treated with various plant extracts has significantly reduced the total carbohydrate content in the haemolymph. Amongst all the extracts evaluated, methanol extract of A. calamus drastically reduced the total carbohydrate content (46.60%) at highest concentration tested, which is far lower than other plant extracts. Out of all the hexane and aqueous extracts of various plants evaluated the A. calamus hexane extract (48.20%) and aqueous extract (48.80%) was far effective than other extracts in inhibiting the carbohydrate contents of P. xylostella haemolymph at 5.00% concentration tested as in controls it was 58.21 (hexane extract) and 58.75% (aqueous extract). All the indigenous plant extracts were proven to be safer to adults of B. hebetor where only maximum of 6.67 per cent mortality was observed at the higher concentration tested and at all the lower concentrations the mortality was nil. However, the grub mortality was lowest of 3.33 per cent at 0.05 and 0.50% concentrations of A. indica and S. nuxvomica aqueous extracts.ThesisItem Open Access STUDIES ON BIOPHYSICAL AND BIOCHEMICAL BASIS OF RESISTANCE IN BRINJAL GENOTYPES AGAINST MAJOR PESTS OF BRINJAL(COLLEGE OF HORTICULTURE DR. Y.S.R. HORTICULTURAL UNIVERSITY VENKATARAMANNAGUDEM, WEST GODAVARI (Dist.) – 534 101, 2017-07-13) SIGIREDDY LEELA PRAVEEN; N. EMMANUELThe present investigation on “Studies on biophysical and biochemical basis of resistance in brinjal genotypes against major pests of brinjal” was carried out during rabi, 2016-17 at College of Horticulture, Venkataramannagudem, Dr. Y.S.R. Horticultural University, West Godavari District. The objective of the study was to screen various brinjal genotypes in order to identify resistant sources against major pests of brinjal and further authenticate their biophysical and biochemical basis of resistance against major pests of brinjal. Out of 44 brinjal genotypes tested, IC-090050 and IC-090199 showed lowest infestation to fruit and shoot borer while Irapaduguda-W showed highest. Based on per cent fruit damage, twelve genotypes viz., IC-090050, IC-090199, EC-169084, EC-316742, EC-316309, IC-089955, EC-316273, Bhagyamathi, IC-090674, EC-169089, IC- 110949 and IC-111392 were found to be moderately resistant to borer damage. The lowest per cent fruit damage by L. orbonalis was observed in the genotype IC-090050 (10.26%) followed by IC-090199 (12.75%), EC-169084 (13.03%) and the lowest per cent shoot damage was observed in the genotype IC-090050 (4.11%) followed by IC-090199 (4.21 %) EC-169084 (4.32%) which were statistically on par with one another. Among 44 genotypes of brinjal tested, none of them were immune to jassid infestation. Nevertheless, one genotypes viz., IC-090050 with 9.90 per cent hopper burn intensity was considered as highly resistant to A.devastans which recorded 1.41 and 2.74 times lesser than Bhagyamathi and Dommeru local respectively in per cent jassid intensity. Least number of whitefly and hadda beetle population per three leaves was noticed in IC- 127074. Out of 44 brinjal genotypes evaluated for biophysical basis of resistance, the genotype EC-169084 recorded the maximum trichome density, which was 1.12 and 1.18 times more than the resistant check Bhagyamathi and Gulabi respectively. The lowest mean value of shoot thickness was noticed in genotypes EC-169084, EC-316742, IC- 090050 and IC-090199 which was statistically on par with Bhagyamathi. The genotype IC- 090050 recorded the maximum calyx length followed by Babajipeta-1, IC-334723 and Gulabi. Maximum pedicel length recorded in the genotype IC-110949, followed by IC- 111322 and IC-336474. Highest fruit diameter was recorded in the genotype Gottivada local (9.61cm), followed by IC-334723 and Babajipeta-1, while the genotype IC-110949 recorded the lowest fruit diameter, which was 1.59 times lesser than Bhagyamathi. The genotype Gottivada local recorded the maximum fruit circumference of 30.98 cm, followed by EC- 316309, IC-126918 and Babajipeta-2, while IC-127071 recorded the minimum fruit circumference of 9.67 cm, which was 0.88 times lesser than Bhagyamathi. Tuni local recorded the maximum fruit yield with 3398.71g which was 8.10 times more than Bhagyamathi (419.07 g) but its marketable yield was 2548.33 g followed by Andra local (2646.86 g), Babajipeta-2 (2597.75 g) and Babajipeta-1 (2273.5 g), while IC- 110949 recorded the minimum fruit yield per plant (251.54 g). The genotype IC-090050 was recorded with the minimum total sugar content of 1.26%, which was 0.63 times lesser than Bhagyamathi. Similarly, highest starch content of 1.54 g/100 g was found in genotype IC-090050 which was 1.11 times higher than Bhagyamathi (1.38g /100 g). Likewise, the genotype IC-090050 recorded the lowest protein content of 0.38 g /100 g, which was 0.84 times lesser than Bhagyamathi (0.45 g/100g). Interestingly, the highest phenol content of 5.18 mg/100 g was found in genotype IC- 090050, which was 1.02 times higher than Bhagyamathi (5.06 g /100 g). Fruit damage by fruit and shoot borer showed significant negative correlation with trichome density (-0.797), internodal length (-0.242), fruit length and width ratio (- 0.249), white fly (-0.425) and hadda beetle (-0.475). Shoot damage by fruit and shoot borer showed significant negative correlation with trichome density (-0.809), internodal length (- 0.257), fruit length and width ratio (-0.254), white fly (-0.458) and hadda beetle (-0.496). High heritability (hb 2) estimates (>60%) coupled with high estimates from genetic gain as per cent of mean (>20%) were observed in fruit weight, number of fruits per plant and fruit yield. Among all the genotypes maximum divergence showed by cluster III and minimum divergence showed by cluster I. Fruit weight, fruits per plant, total sugars and starch content of fruit exerted a high positive direct effect on fruit yield (t/ha). Hence, direct selection for these traits should be effective. The present study on screening of brinjal genotypes, biophysical and biochemical tests conducted, the genotypes IC-090050, IC-090199, EC-169084, EC-316742, EC- 316309, IC-089955, EC-316273, IC-090674, EC-169089, IC-110949, IC-111392, Tuni local, Gottivada local and IC-127074 were found to be resistant against major pests of brinjal.ThesisItem Open Access MOLECULAR INSIGHTS OF POPULATION DIVERSITY, OLFACTION AND DIAPAUSE IN RED BANDED MANGO CATERPILLAR, Deanolis sublimbalis Snellen (CRAMBIDAE: LEPIDOPTERA)(COLLEGE OF HORTICULTURE Dr. Y.S.R.HORTICULTURAL UNIVERSITY VENKATARAMANNAGUDEM, WEST GODAVARI (Dist.) – 534 101, 2017-07-28) GANDHAM KRISHNA RAO; Dr. A. SUJATHARed Banded Mango Caterpillar (RBMC), Deanolis sublimbalis Snellen (Lepidoptera: Crambidae) is a specific pest of mango fruits all over tropical regions of South and South-East Asia. The current management strategies for this pest mainly involve synthetic chemical insecticides. Moreover, the research carried out so far mainly revolves around surveillance, seasonal incidence, biology, dispersal, management protocols, trade impact and quarantine restrictions. Understanding the population diversity, forecasting, mating behaviour, moth emergence periods, pre-pupal diapause and adult olfaction is of critical importance for devising holistic management strategy for D. sublimbalis. Predicting RBMC, D. sublimbalis incidence well in advance with maximum accuracy will contribute to the success of IPM programs in India. The present forecasting model explored the scope of using host-plant phenology and abiotic variables to predict the accurate incidence of RBMC. The current study proposed the variables viz., crop phenology, morning relative humidity, minimum temperature as reliable indicators for predicting the RBMC incidence with significant co-efficient of determination (R2= 0.80) over other variables. Sequential sampling plans were further formulated for efficient detection of RBMC infestation. The decision line of sequential sampling was determined to be d = 10n ± 4.15√n. The weather based forecasting model and sequential sampling plan would facilitate decision-making for spray interventions in effective management of D. sublimbalis. Documenting the nature of population genetic variation, its magnitude and distribution with in a species is essential in understanding their behaviour, response to selection pressure and population structure. Accordingly molecular characterization of different populations belonging to various mango growing regions in India was carried out using the mitochondrial gene, Mitochondrial Cytochrome Oxidase-I (mt COI) and nuclear gene, Elongation Factor 1 Alpha (EF-1α). Phylogenetic analysis of the COI and EF-1α, indicated that no significant molecular diversity across the populations of D. sublimbalis from different geographical locations of India with respect to COI and EF-1α. Earlier studies revealed that, RBMC undergoes pre-pupal diapause during the off-season, a bottleneck not only for continuous laboratory rearing of D. sublimbalis but also for development of control strategies against this notorious pest. Interestingly, moths' emergence was noticed not only during the active fruiting season of the host plant (Mango) but also during the off-season. Further, de novo transcriptome analysis was carried out using the Illumina HiSeq 2500 platform. A total of 179.7 million clean reads were obtained from diapause pre-pupae (DPP), active season pre-pupae (APP) and pupae (P). When the transcripts were annotated against the Swiss port and NCBI nr databases using BLASTX, a total of 24,148 of 45,884 transcripts were annotated. Further analysis of these unigenes was performed using the databases viz., Clusters of Orthologous Groups of proteins (COG), Gene Ontology (GO), and the Kyoto Encyclopedia of Genes and Genomes (KEGG). To identify the significant expression changes in transcripts, a differential expression analysis of transcripts was also conducted through pair-wise comparisons of the three different stages viz., DPP, APP, P. Moreover, three pathways (proteasome, epstein-barr virus infection and lipoic acid metabolism) were significantly (P< 0.01) enriched among the diapause phase. From these three pathways, 25 up-regulated and 1 down-regulated genes were identified during the diapause phase. To date, no diapause related genes were identified in D. sublimbalis. Olfaction plays a fundamental role in modulating the insect behaviors’ such as mating, foraging and oviposition. To understand the response of adult female D. sublimbalis to host plant volatiles, behavioural bioassays were conducted using Y-tube and mini wind tunnel, experimental results revealed that lime stage mango fruit volatiles were significantly (P< 0.0001, Y-tube assay and P< 0.03, mini wind tunnel assay) attractive to female D. sublimbalis moths. Further, the antennal transcriptomes of male and female RBMC were sequenced and characterized. A total of 77 olfactory genes, including 42 odorant-binding proteins (OBPs), 9 odorant receptors (ORs), 11 chemosensory proteins (CSPs) and 15 ionotropic receptors (IRs) were identified as olfactoryrelated genes in D. sublimbalis. The predicted proteins were compared with homologs in other lepidopteran species (Conogethes punctiferalis, Ostrinia furnacalis, Helicoverpa armigera and Spodoptera litura) as well as model insect (Bombyx mori), which showed high sequence homologies between C. punctiferalis, O. furnacalis, B. mori and H. armigera. However, all the 77 olfactory genes were first time reported in this insect and the generated information on D. sublimbalis OBPs, ORs, CSPs and IRs will be useful for future
