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Anand Agricultural University, Anand
Anand Agricultural University (AAU) was established in 2004 at Anand with the support of the Government of Gujarat, Act No.(Guj 5 of 2004) dated April 29, 2004. Caved out of the erstwhile Gujarat Agricultural University (GAU), the dream institution of Sardar Vallabhbhai Patel and Dr. K. M. Munshi, the AAU was set up to provide support to the farming community in three facets namely education, research and extension activities in Agriculture, Horticulture Engineering, product Processing and Home Science. At present there seven Colleges, seventeen Research Centers and six Extension Education Institute working in nine districts of Gujarat namely Ahmedabad, Anand, Dahod, Kheda, Panchmahal, Vadodara, Mahisagar, Botad and Chhotaudepur
AAU's activities have expanded to span newer commodity sectors such as soil health card, bio-diesel, medicinal plants apart from the mandatory ones like rice, maize, tobacco, vegetable crops, fruit crops, forage crops, animal breeding, nutrition and dairy products etc. the core of AAU's operating philosophy however, continues to create the partnership between the rural people and committed academic as the basic for sustainable rural development. In pursuing its various programmes AAU's overall mission is to promote sustainable growth and economic independence in rural society. AAU aims to do this through education, research and extension education. Thus, AAU works towards the empowerment of the farmers.
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ThesisItem Open Access BIOLOGY, POPULATION DYNAMICS AND CONTROL OF HELIOTHIS ARMIGERA HUBNER ON IMPORTANT HOST CROPS IN MIDDLE GUJARAT(AAU, Anand, 1993) Mehta, D. M.; Patel, J. R.Investigations on biology, population dynamics and control of H. armigera on important host crops were carried out during 1990-91 and 1991-92 at the Department of Entomology, Gujarat Agricultural University, Anand Campus, Anand. The effect of larval food was not observed on egg period but larval period was affected. The larval period was shortest on lucerne (Medicaso sativa L.) leaves and longest on chickpea (Cicer arientinum L.) leaves. The maximum and minimum larval survival for both the sexes was . on chickpea pods and chickpea leaves respectively. it was reflected on growth index. The pupal duration on chickpea pods was short. The pupae obtained by rearing the H. armigera larvae on lucerne leaves and chickpea pods were big in size and pupation was very shallow. The adults obtained from lucerne leaves had long oviposition period and high fecundity. The life span for both the sexes was longest onchickpea leaves followed by tomato fruits, pigeonpea pods, tomato leaves, chickpea pods and lucerne leaves. The studies on population dynamics of H. armigera on various crops, weeds, medicinal and ornamental plants revealed ovipositional and larval activity during July to April. The correlation of various abiotic factors with U- armigera activity on pigeonpea showed negative correlation between egg density and soil temperature. Negative and positive association of minimum temperature, vapour pressure and soil temperature was observed with oviposition on tomato and lucerne, respectivly. On pigeonpea and chickpea larval activity was more influenced by soil temperature, whereas, on lucerne minimum temperature, vapour pressure, and soil temperature influence was observed. Considerable activity of an egg parasitoid Trichogramma spp. was found in the fields of tomato, tobacco and pigeonpea in middle Gujarat during October to December. Preliminary studies on resistance in 21 genotypes and 3 local cultivars of tomato to H. armigera revealed low damage to unriped fruits of Karnataka and Mangala and riped fruits of SL 120, F24C8 and Piersol. Karnataka and Mangala had higher marketable fruit yield than others. The degree of fruit damage by H. armigera was positively related with total soluble sugar and negatively with ascorbic acid. Low ovicidal and high ovipositional deterrent effect of neem seed kernel suspension and margoside was found against H. armigera. The spray application of these two botanicals alone as well as combinations with endosulfan at lower concentration gave effective protection to tomato fruits by preventing the larval activity of H. armigera and gave considerably higher marketable fruit yield. The spray application of neem seed kernel suspension with endosulfan had highest increase in yield and avoided 69.33% loss in marketable fruit yield. The residue of endosulfan in/on tomato fruits was quite below the tolerance limit prescribed by FAO/WHO when tomato crop was sprayed with a mixture of endosulfan 0.035% and neem seed kernel suspension (3%). Among the various recommended insecticides, fenvalerate (0.01%) showed quick and high toxicity to H. armigera larvae. The larvae fed on lucerne had higher susceptibility to all the recommended insecticides than the larvae fed on pigeonpea and chickpea.ThesisItem Open Access Bioecological studies on Geocoris ochropterus Fieber (Hemiptera : Lygaeidae) , an important predator in cotton ecosystem(AAU, Anand, 1996) SHARMA, URMILA; Yadav, D. N.Bioecological studies on the big eyed bug, Geocoris ochropterus Fieber, an drnportant predator in the cotton ecosystem, were made during 1994-95 and 1995-96 seasons at the Anand Campus of Gujarat Agricultural University, Anand. Biological observations revealed that the predator laid yellowish white eggs singly on the plant parts which took 8.33 ± 0.27 days at varying temperature of 29.62 ± 0.38 to 30.36 ± 0.12°C, RH 84.26 + 1.25 % and L : D, 12:12 to hatch. Maximum hatching (82 %) was observed when the temperature tanged between 21.61 ± 0.23 to 23.5 + 0.76°C and RH 71.03 + 2.38 %. The predator passed through five nyraphal instars. The duration of the first, second, third, fourth and fifth instar was 5.5 + ©.22, 5.6 ± 0 . 20 , 5.6 + 0.20, 5.9 + 0.33 and 9.25 ± 0.23 days respectively. Total nymphal duration was 29.7 + 1.43 days. Nymphal mortality was high in the fifth instar (39.21 % ). Sexes can be differentiated from their size. Males are usually smaller. The sex ratio in the laboratory population and field population was 1:1.10 (male : female) and 1.29 :1 (male : female) respectively. Mating accomplished easily and lasted for 15m to 4h in the laboratory. The preoviposition, oviposition and postoviposition periods averaged 3.4 ± 0.47, 19.2 ± 2.84 and 3.6 ± 0.69 days respectively of the mated female. Fecundity, when reared on A. gossypii averaged 42.4 + 5.09 eggs. The daily rate of oviposition of laboratory reared female was 1.21 eggs/day and that of field collected female was 0.91 eggs/day. Daily rate of oviposition was greatly affected (6.2 eggs/day) when the females were fed on eggs of Earias vitirella + cotton leaf. Longevity of male and female was 19.9 ±3.68 and 29.5 ± 3.55 days respectively. The female lived longer when fed on eggs of Spodoptera litura + fresh cotton leaves and A. gossypii nymphs + fresh cotton leaves studies on predatory potential showed that maximum consumption was observed during fifth instar. The nymphs consumed an average 1 05 + 4.33 aphid nymphs before reaching maturity. The male and female consumed on an average 530.28 ± 61.74 and 634.14 ± 71.02 nymphs of A. gossypii respectively in their life span. Further, female of G. ochropterus consumed on an average 32.60 and 19.80 eggs of H. armigera and E. vitiella respectively per day. The predator was found to prey on twenty one species of pests occurring on thirteen crops and two weeds but there were about eight species of plants with which it was not found associated. Cannibalism, phytophagy and necrophagy was also observed. G. ochropterus was found fairly well distributed in cotton growing areas of Gujarat. The predator was found relatively free from natural enemies. Only in one case, egg parasitisation by an unidentified eulophid was recorded. The adult was predated upon by an unidentified reduviid bug and a spider. Insecticides such as Methyl-o-demeton, endosulfan, quinalphos, monocrotophos, fenvalerate and cypermethrin, normally used in cotton were found to have detrimental affect on the natural population of the bug. A large population of G. ochropterus survived and flourished on relay crops like maize and sunnhemp and was able to shift to cotton crop which was sown early. The predator appeared to exhibit habitat preference. In nature the predator occurred in the first fortnight of September during 1994-95 and in the second fortnight of August during 1995-96. The predator population reached its peak during the first fortnight of December. The activity of G. ochropterus was found negatively correlated with relative humidity. They remained active until the crop was removed. Off season survival of the predator was recorded on crops ajid weeds like ratoon cotton, maize, sunnhemp, mungbean, okra, brinjal, potato, summer groundnut, cowpea, Chenopodium album and Gyanandropsis spp. Greater population was observed on ratoon cotton, maize, sunnhemp, okra, brinjal, cowpea and lucerne. Developing effective mass rearing techniques and efficient relay cropping system and other methods to conserve the predator in nature are suggested.ThesisItem Open Access BIOECOLOGY, BIOEFFICACY AND RESIDUAL STATUS OF SOME READY MIX INSECTICIDES IN RELATION TO PEST COMPLEX OF OKRA [ABELMOSCHUS ESCULENTUS (LINNAEUS) MOENCH](AAU, Anand, 1997) Shah, Bharat R.; Vyas, H. N.Investigations were carried out on the bioecology, bioefficacy and residual status of ready to use insecticides on okra at B.A. College of Agriculture, Gujarat Agricultural University, Anand, during 1995 and 1996. The population dynamics of insect pests viz., aphids, jassids, shoot arid fruit borer as well as the coccinellid predator were studied in relation to abiotic and biotic factors. The aphid count ranged from 0.48 to 63.51 and 0.91 to 49.28 per leaf during 1995 and 1996, respectively. The correlation and regression studies revealed nonsignificant correlations of abiotic factors with aphid population, however the latter showed highly positive correlation with the biotic factor viz., coccinellid predator, M.sexmaculatus during 1995. The activity of the predator increased with the increase in aphid population.The population of coccinellid predators was absent during 1996.The correlation coefficient analysis revealed that the predator population was negatively correlated with morning and evening vapour pressure as well as with mean vapour pressure.ThesisItem Open Access INTEGRATED PEST MANAGEMENT IN COTTON HYBRID 6(AAU, Anand, 1992) Patel, Jagadishchandra Ramchandra; Yadav, D. N.Studies were conducted to develop integrated pest management in cotton Hybrid 6 in Middle Gujarat conditions at Anand Campus, of Gujarat Agricultural University during the years 1989-90 and 1990-91. Experiment was laid out in Exploided Block Design with fifteen observations in each treatments. The IPM treatment consists of integration of application of phorate 10 G in soil @ 1 kg a.i. ha, planting of maize/sorghum on the border of cotton plot, spot application of monocrotophos 0.036 per cent against sucking pests of cotton, releases of Trichogramma chilonis Ishii @ 200000/ha and Chrysopa scelestes Bank @ 100000/ha at weekly interval alternately and need base application of triazophos 0.05 per cent were tested and compared with recommended insecticidal control measures and control. The results indicated that the insecticidal treatment on need base had the lowest number of sucking pests viz.. Aphis gossypii, Amrasca biguttulla biguttulla, Thrips tabaci arid Bemisia tabaci throughout the season as compared to IPM and control. In IPM treatment, soil application of phorote 10 G was effective in checking the population of A. gossypli and A. biguttulla biquttulla in early part of the season. Moreover, due to inundative five releases of Chrysopa, these pest could not build up pestiferous population as the mean population of A. gossypii and B. tabaci were 5.72 and 3.58 per lesf in IPM as against 7.22 and 4.77 adult per leaf in control treatment respectively. In IPM treatment, releases of Trichoqramma, Chrysopa and other naturally occurring bioagents viz., Roqas aliqarhensis were effective in checking the population of Earlas vittella as mean damage in square, green bolls, openbolls, locules and shed material was recorded 6.04, 9.05, 16.66, 20,97 and 14,51 per cent as against 12.74, 19.33, 22.83, 30.17 and 27.05 per cent in control treatment respectively. Heliothis population was too meagre to cause any serious damage during both the years. Six species of predators viz., Menochilus sexmaculatus, Brumus sutaralis, Coccinella septempunctata (all coccinellids), Chrysopa scelestes (Chrysopidae) Geocoris bicolor (Lygeidae), Paederus fuscipes (staphylinid) syrphidfly and piredatory spiders were encountered on maize, whereas coccinellids, Chrysopa and predatory spiders were encountered on sorghum planted on the periphary of cotton plots which indicated that a large number of natural enemies was found on the maize than sorghum and most of them happen to be the common predators pests in the cotton ecosystem, the maize served as reservoir for the natural enemies. Therefore, maize surrounding cotton plots is recommended for the conservation of the naturally occurring parasites and predators, thereby allowing them to exert natural control of the cotton pests. From the pooled data, it could be seen that the insecticidal treatment had recorded the highest yield (2063 kg/ha) and was at par with IPM treatment (1648 kg/ha), whereas control treatment had recorded significantly lowest yield (1107 kg/ha). The highest incremental cost benefit ratio (ICBR) was obtained (1:4.07) in IPF: treatment as against (1:2,40) in insecticidal treatment on the basis of pooled data of two years. The correlation coefficient studies indicated highly significant negative correlation between incidence of A. gossypii, A. biguttulla binuttulla, T. tabaci , B. tabaci percentage damage to squares by E. vittella and Meliothis, percentage damage to green bolls , openbolls, locules by E. vittella was yield of seed cotton. This indicated perfect relationship between yield of seed cotton with pest incidence. The pest population has significant effect on reduction of yield. Thus, from the yield, expenditure, conservation of natural enemies and I.C.B,R. view points,it could be concluded that IPM is the realistic approach for better management of the cotton pests and its adoption in large areas will go a longway in reducing pesticidal use in the environment and will help preserving ecology.ThesisItem Open Access BIO-ECOLOGY OF SERPENTINE LEAFMINER, LIRIOMYZA TRIFOLII (BURGESS) (DIPTERA : AGROMYZIDAE) AND MANAGEMENT OF LEAFMINER AND FRUITBORER ON TOMATO LYCOPERSICON ESCULENTUM (MILL.)(AAU, Anand, 1999) JYANI, D. B.; PATEL, J. R.Investigations on host plants, population dynamics, bio-efficacy of botanical and synthetic insecticides against Liriomyza trifolii Burgess and it's natural enemies were carried out and Integrated Pest Management (IPM) modules for tomato were evaluated at Gujarat Agricultural University, Campus Anand during 1995 to 1999. In middle Gujarat L. trifolii was recorded on 57 host plants which include fibre, pulses, vegetables, fodder, oilseeds, spices and condiments crop as well as medicinal and ornamental plants. It's incidence was relatively more on smoothgourd, bottlegourd, cowpea, cucumber, mustard, muskmelon, watermelon, pointedgourd, pumpkin, kaligeeri, abvel, wallflower and lobelia. The pest remained active throughout the life of tomato (Lycopersicon esculentum mill), whereas on castor (Ricinus communis L.) and marigold (Tegetes erecta L.) activity was found from August to February and July to December respectively. During 1995-96 the activity was high in the 1st week of December, 3rd week of December and 3rd week of November on tomato, castor and marigold respectively, whereas during 1996-97, the pest population was at peak in lst week of October, 1st week of November and 3rd week of November on tomato, castor and marigold respectively. The pest population of L. trifolii on tomato, castor and marigold had positive and significant correlation with bright sunshine hours and negative correlation with minimum and mean temperature, relative humidity, vapour pressure and rainfall. The activity of L. trifolii was found on 12 weed plants with peaks in the 2nd fortnight of August and 1st fortnight of September during 1995-96 and 1996-97,respectively. The incidence was relatively more on shevary (Sesbania sesaban L.), chanak chibhdi (Mukia maderaspatana L.) and carvellweed (Gynandropsis pentaphylla L.). Spray of cyromazine @ 225 g a.i./ha and Neem (Azadirachtin indica A. juss) Seed Kernel Suspension (NSKS) 5 per cent proved effective against L. trifolii and Heliothis armigera Hb. and gave higher yield. Endosulfan 140 g a.i./ha, dimethoate 120 g a.i./ha, methyl-o-demeton 100 g a.i./ha proved equal effectiveness as cyromazine 90 g a.i./ha. The highest avoidable loss was found in a tomato crop protected .with cyromazine @ 45 g a.i./ha, whereas lowest with NSKS 5 per cent spray. Spray of NSKS 3 per cent and azadirachtin based formulation Gronim 0.3 per cent found effective against L. trifolii and H. armigera and yielded higher marketable fruit yield. Azadirachtin based formulations Neemol, Parasmani and Neemark as well as nicotine sulphate showed equal effectiveness and gave almost equal yield. Tomato crop protected with Naffatiya (Ipomoea fistulosa) Leaves Extract Suspension (NFLES) 3 per cent had highest avoidable loss followed by Parasmani 0.3 per cent, whereas lowest with NSKS 3 per cent and Gronim 0.3 per cent among plant materials and botanical formulations respectively. The activity of larval parasitoid (Chrysonotomyia spp. ) of L. trifolii was started from September on tomato, castor and marigold, but its activity was continued for a longer period on tomato and marigold than castor, whereas activity of larval pupal parasitoitl (Gronotoma spp.) remained for a shorter period on these three crop. It was higher on castor followed by marigold and tomato. The positive influence of temperature and morning vapour pressure was found on activity of Gronotoma spp. on castor, while Chrysonotomyia spp. had negative correlation with rainfall and morning relative humidity in tomato field. Spray of cyromazine 0.075 percent and abamectin 0.009 per cent proved effective against L. trifolii on tomato, castor and marigold. NSKS 5 per cent found least toxic to Chrysonotomyia spp. and Gronotoma spp. in tomato field, whereas cyromazine, abamectin and NSKS found equally toxic to Gronotoma spp. in castor field. The equal toxicity of cyromazine and NSKS to Chrysonotomyia spp. was found on marigold. Cyromazine' and endosulfan were found equally toxic to both the parasitoids whereas methyl-o-demeton was found less toxic to Chrysonotomyia spp. than dimethoate on tomato, castor and marigold. Integrated Pest Management (IPM) module Ma consisting intercropping of tomato with African marigold (T. erecta), installation of sexpheromonetrap for H. armigera along with spray of NPV, NSKS and endosulfan coupled with three releases of Trichogramma dhilonis was found effective against L. trifolii and H. arniigera and gave higher yield than module M1 and M2. The egg, larval, pre-pupal, pupal and adult stages of L. trifolii were shorter on castor than tomato and marigold, whereas fecundity was higher on castor than marigold and tomato, latter two had equal fecundity. The life span of male and female remained shorter on castor than marigold and tomato. The cent per cent emergence of adult L. trifolii was observed when pupae burried up to 5 and 10 cm depth of dry and wet soil respectively. The adult could not emerge from a pupae burried at a depth of more, than 25 cm.ThesisItem Open Access STANDARDISATION OF MASS REARING OF MALLADA BONINENSIS OKAMOTO (NEUROPTERA: CHRYSOPIDAE) AND ITS UTILIZATION AS ONE OF THE COMPONENTS OF INTEGRATED PEST MANAGEMENT IN COTTON(AAU, Anand, 1993) PARASARA, U. A.; YADAV, D. N.Studies on standardisation of mass rearing of Mallada boninensis Okamoto (Neuroptera : Chrysopide) and its utilization as one of the components of integrated pest management in cotton pests were carried out during 1990-93. The results revealed that M. boninensis can be mass reared by following either two phase rearing in multicelled plastic louvers or single phase rearing in Biosec bioassay trays. The pupal recovery in both the methods was 67.09 and 71.56 per cent, respectively. Majority of adults were observed to emerge between 12 p.m. to 2 a.m.ThesisItem Open Access VARIETAL RESISTANCE AND INTEGRATED MANAGEMENT OF SPODOPTERA LITURA FABRICIUS IN CASTOR(AAU, Anand, 1999) Thanki, K. V.; PATEL, J. R.To develop Integrated Management strategy for leaf eating caterpillar, Spodoptera litura Fab. (Noctuidae : Lepidoptera) on castor, Ricinus communis L. cultivated in middle Gujarat agroclimatic conditions, studies were carried out during 1997-98 and 1998-99 on varietal resistance, activity of S. litura and its larval parasites and effect of different varieties of castor on development and fecundity of S. litura. Study of 12 castor varieties/hybrids in comparison to GAUCH-1 for their resistance to S. litura under unprotected condition revealed the least preference of GCH-4 and GCH-5 for oviposition by S. litura female moths than rest of the varieties, whereas castor VI-9 and GAUCH-1 were more preferred for egg laying., by S. litura. Larval population on different castor varieties/hybrids also found in a same trend as observed for oviposition. The lowest leaf damage caused by S. litura larvae was observed in castor varieties GCH-4 and GCH-5, whereas the highest leaf damage was observed in varieties SKI-73, VI-9 and GAUCH-1. The leaf damage by S. litura was found higher in castor varieties VP-1, SH-72, 48-1, VP-1 and Geeta than CO-1, DCS-9 and JI-35. The positive correlationship was found between the larval population and leaf damage caused by S. litura in castor field. The larval development of S. litura was adversely affected on GCH-4 and GCH-5 in comparison to castor VI-9 and GAUCH-1. The higher mortality of first instar larvae was found within two days when fed on GCH-4 and GCH-5. The higher fecundity was observed on castor VI-9 than castor SH-72, SKI-73, 48-1 and GAUCH-1. The presence of higher quantity of total soluble sugars, total amino acids and lower quantity of peroxidase and polyphenol oxidase in the leaves of castor varieties VI-9 and GAUCH-1 enhanced the feeding activity of S. litura larvae in comparison to GCH-4 and GCH-5. The egg and larval populations as well as castor leaf damage of S. litura larvae in IPM module M3 and modules M1 and M2 where synthetic insecticides were sprayed on need and scheduled basis respectively remained almost equal which indicated the effectiveness of all the three IPM components viz., spray of SINPV @ 250 LE/ha and NSKS 3 per cent and release of C. scelestes larvae @ 20000/ha. The higher effectiveness of IPM module (M3) against S. litura reflected on the yield and showed the highest ICBR at Anand and Nawagam locations. The activity of larval parasite Chelonus formosanus on S. litura was found during second to fifth week of October and from first week of September to second week of December during 1997-98 and 1998-99, respectively. The activity of Apunteles beneficus was found in the second week of October to first week of January and in the fifth week of October to first week of January during 1997-98 and 1998-99, respectively. Vapour pressure (morning and evening) and relative humidity showed negative influence on activity of A. benefeicus, whereas bright sunshine hours, maximum and minimum temperature, vapour pressure (morning and evening) and relative humidity (evening) had positive effect on activity of C. formosanus.ThesisItem Open Access GENETIC STUDIES FOR VARIOUS BIOLOGICAL TRAITS IN Chrysoperla carnea STEPHENS (Neuroptera : Chrysopidae)(AAU, Anand, 1996) Patil, Yashwant Raghunath; YADAV, D. N.The present investigation was carried out to study the genetic variability in the six parental populations of ChryBoperla carnea Stephens originally collected from six different geographical regions of India, and the magnitude of heterosis, combining ability, gene actions and components of genetic variances following Griffing (1956a, 1956b) and Hayman (1954a, 1954b, 1958) approaches in diallel crosses involving above six parental populations at Biological Control Laboratory of Gujarat Agricultural University, Anand Campus during 1993-1995. The results on genetic variability revealed the presence of wide genetic variability for most of the biological traits in the parental populations of C. carnea studied. High heritability coupled with high genetic advance observed for post-oviposition period, fecundity and oviposition period suggested that phenotypic selection would be very effective for the improvement of these traits. Mean squares due to parents, hybrids and parents Vs. hybrids revealed significant differences for most of the traits under study. Based on the mean performance for various bioLogicaL traits, Anand population (A) proved to be the best followed by Aurangabad (AU), Jalgaon (J) and Hisar (H) populations Among crosses, AxS and AxAU proved to be the best crosses which involved Anand population (A) as one of the parent. The results on the magnitude of heteroeia supported the idea of exploitability of hybrid vigour in C. carnea for commercialiasation of the predator. The crosses viz., AxS, BxAU, AUxS, AUx J, BxJ, SxJ, SxH and JxH showed high magnitude of heterosis and heterobeltiosis for many of the important biological traits which can further be exploited in future breeding programme. In the present study, diallei assumptions were met for all the biological traits except feeding potential and pupation. Analysis of variance for combining ability revealed both additive and non-additive gene actions were responsible for the inheritance of majority of biological traits under study. However, the ratio of ogca2/osca2 suggested the preponderance of additive gene action for all the characters except male longevity, fecundity, feeding potential, pupation, pupal duration and larval tolerance to monocrotophos for which non-additive gene action was more pronounced. Among parents, Anand (A), Hisar (H) and Aurafigabad (AU) populations showed significant desirable gca effects while among the crosses, AxB, AxAU, AxS, BxJ, SxJ and JxH exhibited significant desirable sea effects for many of the biological traits. Components of variance analysis showed larger magnitude of dominance components and presence of over dominance for all the biological traits under study. Graphical analysis revealed considerable genetic variability and diversity, over dominance, asymetrical gene distribution and complementry type of epistatis for majority of the biological traits studied. The heritability estimates were low for majority of the biological traits except adult emergence and larval duration where moderate to high heritability estimates were observed. Overall study revealed the presence of great deal of genetic variability and diversity for majority of the biological traits studied. Since, diallel analysis following both Griffing and Hayman approaches revealed the importance of both additive and non-additive gene actions for the inheritance of majority of the biological traits under study, cyclic method of breeding/recurrent selection would profitably be employed for the improvement of these traits. High magnitude of heterosis and heterobeltiosis observed for many of the important biological traits studied also suggested the feasibility of utilizing hybrid vigour on commercial scale.ThesisItem Open Access STUDIES ON GENETIC IMPROVEMENT OF GREEN LACE WING CHRYSOPA SCELESTES BANKS (NEUROPTERA : CHRYSOPIDAE) : SELECTION FOR MONOCROTOPHOS RESISTANCE(AAU, Anand, 1993) PATEL, I. S.; YADAV, D. N.Studies were carried out to develop genetically improved monocrotophos resistant strain of green lace wing, C. scelestes during 1989-92 at Biological Control Laboratory of Gujarat Agricultural University, Anand Campus. Monocrotophos was selected as test insecticide because it proved effective against jassids as well as very toxic to C. scelestes and commonly used in cotton ecosystem. Severe pathological changes were observed when histopathological studies were conducted. Of the three bioassay methods tried, topical application was found better and with insecticidal pressure for 9 generations, the strain could be improved to resist 0.047% of monocrotophos. This method gave higher resistance index (442.38). While at same number of generation, food impregnation and film exposure method, showed 4.06 and 1.00 resistance index respectively. The dosage mortality regression lines moves to the right in successive generation and consequently the LC50 value increases. The resistance developed in C. scelestes was observed to reverse in third generation when selection pressure of insecticide was relaxed. Resistance index was 12.518 and 15.44 for R/P and R/S respectively. The monocrotophos resistant strain showed cross resistance to dimethoate 0.03%, acephate 0.075%, phosphamidon 0.03% and methyl-o-demeton 0.03%, but did not show resistance to quinalphos 0.05%, triazophos 0.05%and amitraz 0.1% through belonged to the same group. Possible explanations are given. Biological studies revealed that the larval period was significantly shorter in resistant strain as compared to susceptible strain. Similarly pre-oviposition, oviposition and post-oviposition was also lower in resistant strain. The resistant female laid lesser number of eggs. Morphometric differences were also observed in the larval and pupal stage. Biochemical analysis revealed that resistant strain had higher amounts of I lipids and higher activity of Acetyl cholineesterase enzyme (AchE) than the susceptible strain. Possible reasons for imparting resistance are explained in detail. Genetic analysis of monocrotophos resistance showed that additive as well as epistasis type genes were found to play important role in the expression of larval length of first instar. Toxicological tests revealed that additive as well as non-additive gene effects controlled the expression of this trait. It suggested the polygenic nature of inheritance for monocrotophos resistance in C. scelestes. The collection of C. scelestes from different geographic regions showed wide variation in their biological characteristics and response to monocrotophos. Resistant as well as susceptible strain integrated with monocrotophos gave effective control of aphids and jassids when open and confined releases were made. However, susceptible strain proved ineffective against B. tabaci confirming its susceptibility to monocrotophos. The resistant strain remained unaffected by monocrotophos and gave effective control of B. tabaci. The monocrotophos resistant strain of C. scelestes and its ability to cross resist to some of the insecticides, offers great scope for developing a sound integrated pest management approach in general and particularly in cotton ecosystem.