6 research outputs found
Field evaluation of Musa germplasm for resistance against banana stem weevil, Odoiporus longicollis (Oliver) (Curculionidae: Coleoptera) in Kadapa district of Andhra Pradesh
Banana germplasm with 17 different accessions for resistance were screened against banana stem weevil, Odoiporous longicollis in Koduru region of Kadapa district (Andhra Pradesh). All the accessions had infestation of stem weevil but with varying percent infestation. The 17 accessions of germplasm had weevil infestation ranging from 10.0–100 percent in 2012 with maximum infestation of 100 percent in red banana (AAA genome) followed by Bontha selection-88.88 % (ABB), Karpuravalli-84.60% (AAB) and Ellakibale-64.7% (AB) and the lowest was inSugandhalu-10.00% (AAB). In the year 2013, the infestation was in the range of 13.00-90.40% and with respect to infestation levels in different accessions, and the trend remained same as the earlier year wherein the highest infestation was recorded in red banana-90.40% followed by Bontha selection with the damage of 83.50 %, Karpuravalli (79.80%), Ellakibale (70.00%) and least in Sugandhalu-13.0% (AAB). There was no correlation between number of adults observed and percent damage and similarly no relation can be drawn between percent infestation and height of oviposition, This implies that the infestation caused by the weevils varied in different genotypes and also this information will be further helpful in selecting the resistant germplasms for future
Specific identification, biology and symptoms of whitefly species infesting sunflower in South India
Whitefly species related to sunflower was identified as Bemisia tabaci (Gennadius). Further the identified whitefly species was confirmed to be indigenous B. tabaci on molecular basis by using B-biotype specific SCARs and biological silver leaf assay on sensitive pumpkin (cv Big variety). None of the whitefly samples could positive for the presence of B biotype. The results of the study on the pest life cycle under the laboratory conditions showed that, B. tabaci passed through four nymphal instars before the adult stage. The mean duration values of these stages were 5.6, 4.2, 4.4 and 5.6 days respectively. The total duration of the life cycle of B. tabaci ranged from 23- 42 days at the temperature of 29±2°C with a mean of 34.5. The damage to sunflower crop caused by the whitefly species is discussed with a special emphasis on its ability to transmit leaf curl viral disease
Built in refuge for the management of Pink Bollworm, Pectinophora gossypiella Saunders (Gelichidae: Lepidoptera) in Bt cotton
Field experiment was conducted at the Main Agricultural Research Station, University of Agricultural Sciences, Raichur during 2012-13 to identify and evaluate the suitable refuge strategy systems for pink bollworm resistance management in Bt cotton (Gossypium hirsutum L.) cultivation. The experiment was laid out in randomized complete block design with nine refuge systems : 0 % N-Bt (BIR), 5 % N-Bt (BIR), 10 % N-Bt (BIR), 15 % N-Bt (BIR), 20% N-Bt perimeter refuge, 100% Non Bt, 50% Non Bt, 10% structured refuge and 20% structured refuge as treatments with three replications in replacement series. Significantly lowest incidence (3.55 larvae/plant) and number of bolls with exit holes (11.22) due to pink bollworm was recorded in 0% BIR (41.25 q/ha) followed by 5 % N-Bt (BIR) with yield of 38.74 q/ha and this was on par with 10 % N-Bt (BIR) with yield of 37.79 is next best refuge systems with Bt cotton for higher production and greater economic benefits
Impact of Cluster Frontline Demonstrations on Yield of Chickpea (Cicer arietinum L.) in Prakasam District of Andhara Pradesh, India
The Cluster Front Line Demonstrations (CFLDs) offer a unique approach to establish a direct interface between farmers and researchers, where the latter are involved in planning, executing, and monitoring the demonstrations. The objective of the current study was to evaluate the impact of front line demonstrations conducted for chickpea crop in the Prakasam district of Andhra Pradesh state. Chickpea (Cicer arietinum L.) is a highly nutritious legume crop that is widely recognized as both a health food and a high-return crop. The front line demonstrations were conducted at the farmers’ fields to showcase the production potential and economic benefits of improved technologies. The findings revealed that the implementation of improved cultivation practices recommended under CFLDs, such as the use of recommended varieties, appropriate seed rate, timely sowing, and plant protection technology, resulted in a significant increase in gram crop yield compared to the check plots. The adoption of improved technologies led to higher yields, recording chickpea yields of 21.25, 21.75, and 19.50 q/ha during 2018-19, 2019-20, and 2020-21, respectively, which were 13.35%, 24.37%, and 22.22% higher than the prevailing farmer's practice. The average seed yield under improved practice (IP) was 20.83 q/ha, which was 15.48% higher than the farmer's practice (FP). The technology gap and extension gap ranged from 3.25 to 5.50 q/ha and 1.50 to 4.25 q/ha, respectively. The technology index value varied from 13.0% to 22.0% during the study period. The benefit-cost (B: C) ratio ranged from 2.23 to 2.84 under demonstration, while it was 2.15 to 2.57 under control plots. The average B: C ratio under IP (2.53) was 39.89% higher than that under FP
Evaluation and Performance of Integrated Crop Management in Chilli in Rainfed Tracts of Prakasam District, Andhra Pradesh, India
Chilli is an important high value spice crop, its integrated crop management is an important area for the welfare andlivelihood security of farmers. Most of the farmers of Prakasam district of Andhra Pradesh are growing wide varieties and cultivars of chilli but so far the research findings on chilli integrated crop management were less aware. To know the yield potential of integrated crop management and its economic impact, evaluation on integrated crop management was conducted at Chandhaluru and Nallaguntla Guedm villages. The adopted package of practices was seed rate @1kg/ha, spacing 60x45cm, FYM 15t/ha, Urea, single super and muriate of potash256:150:80 kg/acre. There was wide variation between integrated crop management and farmers practice in fruit yield and economic returns. The results on yield and economic returns indicated that chilli integrated crop management was found superior to farmers practice. Integrated crop management could obtain 124 fruits per plant and yield of 47.00q/ha, thirps incidence (24.3%), whitefly incidence (9.67 %) and fruit rot infestation (6.0%). Whereas,in farmers practicefruits obtained were99per plant and yield of 43.00q/ha, thripsincidence (44.67 %),whiteflyincidence (28.33) and fruit rot(18 %) with a net income of Rs220000/- and B:C ratio 1: 1.88 compared to farmers practice with a net income of Rs113333/-with B:C ratio 1:1.36. The integrated crop management percent yield increased over farmers practices8.5 per cent. It was concluded that integrated crop management could help to improve the economy of the farmers