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Present paper deals with the morphomatric analysis, incidence and biology of leaf eating caterpillar, Diaphania indica, carried out on cucurbits in arid region. The incidence of leaf eating caterpillar was first reported on fruits of different cucurbits and highest fruit infestation was recorded in muskmelon followed by round melon and watermelon fruits at farm of ICAR-CIAH, Bikaner. Eggs are laid on leaves or young shoots or fruits. The female fly laid the eggs in the cavities made by the ovipositor, just beneath the skin of the fruit. The pooled mean duration of the different stages of D. indica viz., the female fecundity (163.35 number), egg period of 3.59 days, larval period of 9.10 days, pre-pupal period of 2.14 days, pupal period of 9.33 days and adult longevity of 10.08 days, respectively. The length of Ist instar larvae is 4.30 ± 0.135 mm and width is 0.53 ± 0.019 mm. The fifth instar larva is 18.10 ± 0.125 mm length and 3.28 ± 0.043 mm width. Pupa is 13.66 ± 0.088 mm length and 2.28 ± 0.043 mm width. Adult female body length was 11.19 ± 0.211 mm and width 24.54 ± 0.201 with wing expansion. The male body length is 11.00 ± 0.159 mm and width 22.85 ± 0.156 mm with wing expansion. The morphometric variations of different life stages of the D. indica have been recorded. Growers can adopt this study for the timely management of D. indica in arid condition.

Out of 103 microsatellite markers used for studying the genetic diversity among local landraces of Luffa species, 56 were found polymorphic, including 38 gSSR and 18 eSSR, respectively. A total of 197 amplification products were obtained. The mean number of alleles per locus was 3.52. The PIC ranged from 0.037 to 0.986, while size of amplified product ranged from 105 to 500 bp. Cucumber-derived SSRs were amplified within L. acutangula (68%), L. aegyptiaca (61.16%), and L. hermaphrodita (60.2%), with an average of 63.12% cross-transferability. The Jaccard's coefficient ranged from 0.66 to 0.97, with an average of 0.81. High genetic variability was observed for node of 1st hermaphrodite flower (6.4-17), days to 1st hermaphrodite flower (38-52.1), days to 1st fruit harvest (43-65), number of fruit per cluster (1-5.9), fruit length (3.9-25 cm), fruit weight (18.4-175 g), number of fruit per plant (20-147.5), and yield per plant (2.2-4.7 kg). Two sub-populations were identified including 21 genotypes (sub-population I) and 06 genotypes (sub-population II), these two sub-populations showed 0.608-0.395% of the ancestral relationship to each other. This study provides information for future exploration, collection, and utilization of Luffa genotypes, as well as the polymorphic markers identified could be available for the study of landmarks in linkages, genomic structures, evolutionary ecology, and marker-assisted selection (MAS) in Luffa species.

Host plant resistance is an important component for management of the melon fruit fly, Bactrocera cucurbitae (Coquillett), owing to difficulties associated with its chemical and biological control. Various biochemical traits including total sugar, reducing sugar, non-reducing sugar, tannins, phenols, alkaloids, flavinoid and pH contents of fruit were studied on 11varieties/ genotypes of muskmelon, Cucumis melo L., in relation to resistance against B. cucurbitae under field conditions. Significant differences were found in tested varieties/ genotypes for fruit infestation and larval density per fruit. AHMM/BR-1, RM-50 and AHMM/BR-8 were the most resistant; MHY-5, Durgapura Madhu and Pusa Sarabati were moderately resistant; AHMM/BR-13, Pusa Madhuras and Arka Jeet were susceptible; whereas Arka Rajhans and GMM-3 were the highly susceptible varieties/ genotypes to fruit fly in both seasons, 2011 and 2012. The larval density per fruit increased with an increase in percent fruit infestation and there was a significant positive correlation (r = 0.97) between percent fruit infestation and larval density per fruit. Total sugar, reducing sugar, non-reducing sugar and pH were lowest in resistant and highest in susceptible varieties/ genotypes, whereas tannins, phenols, alkaloids and flavinoid contents were highest in resistant and lowest in susceptible varieties/ genotypes. Total alkaloid and pH contents explained 97.96% of the total variation in fruit fly infestation and 92.83% of the total variation in larval density per fruit due to alkaloids and total sugar contents.

The crossability between Brassica tournefortii (TT, 2n = 20) and Brassica rapa (AA, 2n = 20) and the cytomorphology of their F1 hybrids were studied. Hybrids between these two species were obtained only when B. tournefortii was involved as a female parent. The hybrid plants were intermediate for most of the morphological attributes and were found to be free from white rust under field conditions. The F1 plants showed poor pollen fertility, although occasional seed set was achieved from open pollination. Self-pollination or backcrosses did not yield any seeds in these plants. The occurrence of chromosome association ranging from bivalents (0–7), trivalents (0–2) to a rare quadrivalent (0–1) in the dihaploid hybrids indicates pairing between the T and A genomes. The homoeologous pairing coupled with seed set in the F1 plants offer an opportunity for interspecific gene transfers from B. tournefortii to B. rapa and vice-versa through interspecific hybridization.

Amphidiploid Raphanofortii was synthesized by colchicinization of the F1 hybrid Brassica tournefortii (TT, 2n = 20)×Raphanus caudatus (RR, 2n = 18). The crossability between these two species, and the cytomorphology of the F1 plants and the amphidiploids were investigated. Intergeneric hybrids between the species were obtained only when B. tournefortii was involved as female parent. The hybrid plants were intermediate for most of the morphological attributes and showed very low pollen fertility compared to the parents. Although a majority of the pollen mother cells of the dihaploid hybrid (TR, 2n = 19) harboured univalents, a maximum of six bivalents were also observed. Of the 37 colchicine-treated F1 plants analyzed cytologically, 21 were found to be true amphidiploids (2n = 38), whereas seven were mixoploids. Meiosis in the amphidiploids was characterized by the occurrence of 19 bivalents, though multivalents and univalents were also observed in a few cells. Most of the amphidiploid plants exhibited a fairly high pollen and seed fertility, which was further enhanced with the advancement of generations. Out of 69 plants investigated in the A2 generation, 64 were euploids while the remaining five were aneuploids (2n = 36, 37, 39, 40 and 42). The newly synthesized Raphanofortii has great potential as a new commercial crop, as well as a bridge species for the transfer of economically important attributes of both the species to other Brassicas.

Seventeen bottle gourd genotypes such as Pusa Naveen, Pusa Samridhi, Udaipur Local, Pusa Santushti, Pusa Sandesh, PSPL, Chomu Lo-cal, Azad Harit, Panchmahal Local, Arka Bahar, Thar Samridhi, PN-22, DBG-5, DBG-6, Jodhpur Local, IC-567538 and Sriganganagar Local were evaluated for resistance against Alternaria blight during rainy season of 2011 and 2012 under field conditions. Among them, 06 varieties such as Pusa Naveen, Pusa Samridhi, Pusa Sandesh, Pusa Santushti, Arka Bahar and PSPL showed moderately resistant having 4.87–8.62% disease severity and 10 genotypes were categorized as moderately susceptible (13.0 to 24.75%) while one germplasm ‘Chomu Local ’proved suscepti-ble against this disease.