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On-farm trials were conducted for the evaluation of IPM modules in cotton against the whitefly Bemisia tabaci (Gennadius) by the Krishi Vigyan Kendra, Bathinda and Mansa at five locations during 201718 and 2018-19. The modules included neem-based insecticides along with detergent powder, darek (Melia azedarach L.) extract and the University recommended insecticides compared with that of farmers’ practice of mixing of non-recommended insecticides. The data revealed significantly maximum reduction (80.0- 85.1% and 80.9- 85.4%) in the incidence of adults compared to the University recommended practice (Mj) at Bathinda and Mansa, respectively. This was followed by module (Mj) comprising use of home-made darek extract (54.4 to 63.3% at Bathinda and 58.0 to 72.5% at Mansa). Module (M3) comprising of addition of detergent powder in neem-based spray solution remained on a par with M with 55.8 to 62.7 and 57.4 to 71.9% reduction in incidence over untreated check. Farmers’ practice of spraying non-recommended insecticides resulted in minimum reduction in incidence (16.7 to 23.1% and 23.6 to 36.3%, at Bathinda and Mansa, respectively). The trend in yield was similar to the above, with maximum being in M4 followed by Mj and M3 with the least yield being with the module comprising of use of non-recommended sprays by the farmers. Maximum number of spray applications (5-6) were given in M4 (farmer’s practice). Maximum and minimum B: C ratio was obtained with the modules M4 (1.3 to 1.5) and M4 (0.8 to 1.2), respectively.

Water hyacinth (Eichhornia crassipes) biomass is an ideal feedstock for bioethanol production as it is rich in hemicelluloses and the lignin content is low. This feedstock is, therefore, a good source of reducing sugars (C5 and C6). Water hyacinth plants were collected from five sites selected along the river Yamuna: A. Okhla West; B. Okhla East; C. Okhla Barrage; D. Najafgarh Drain; E. DND Flyover. As feedstock plants growing in different conditions of water quality in Delhi exhibited different sugar content, a comparative study reveals that plants from site A (Okhla West) possessed maximum reducing sugar content. The sugar content in plants growing in different sites was: A>B>C>D>E. Maximum saccharification (sugar extraction) was obtained after 3% sulfuric acid pretreatment for 1.5 hours at 121°C. Optimization of acid pretreatment helps in breaking strong linkages between hemicellulose and lignin, thereby making the feedstock more accessible for further enzymatic hydrolysis.

Eleven types of yellow sticky traps (15x30 cm) made up of different base and sticky materials were evaluated to determine their persistence and attractancy for greenhouse whitefly Trialeurodes vaporariorum (Westwood) in tomato under polyhouse during summer, rainy and winter cropping seasons. Base materials like yellow coloured thick paper and yellow painted galvanized iron sheet, and sticky materials like castor oil, mustard oil, linseed oil and white lithium grease were evaluated.The cumulative adult catches on traps evaluated remained significantly maximum (594.3 to 1118.0) during rainy season. Use of paper sheet smeared with different pasting materials resulted in significantly more trap catches, compared to the use of iron sheet. Irrespective of the base material, traps smeared with castor oil proved significantly superior followed by that of mustard oil, linseed oil and white lithium grease. The cost of traps ranged from Rs 165 to Rs 2025/cropping season of 140 days/250 m2 polyhouse; with the minimum and maximum being for the white lithium grease pasted on plastic sheet and commercial trap, respectively. The trap with castor oil pasted on paper sheet was good in efficacy but not cost effective. Trap with mustard oil pasted on paper sheet was one of the efficacious traps, and also cost effective.

Improving soil organic carbon (SOC) and nitrogen (N) in arable soils is one of the important strategies to enhance soil quality for sustainable crop production and to mitigate climate change. Hence, we investigated the changes in SOC and N under conservation agriculture (CA) in an alluvial soil of the north-western Indo-Gangetic Plains (IGP) after two years of rice (Oryza sativa L.)-wheat (Triticum aestivum L.) rotation. The treatments were: Puddled transplanted rice followed by conventional-till wheat (TPR-CTW), TPR followed by zero-till wheat (TPR-ZTW), Direct-seeded rice followed by ZTW (DSR-ZTW), DSR-ZTW with rice residue retention in ZTW (DSR-ZTW+RR), DSR-ZTW with Sesbania brown manuring (DSR+BM-ZTW), DSR+BM-ZTW+RR, DSR-ZTW with ZT summer mungbean (greengram) (Vigna radiata) as a relay crop and mungbean residues retained on rice fields as in-situ green manuring (MBR+DSR-ZTW-ZTMB) and MBR+DSR-ZTW+RR-ZTMB. Results indicated that plots under CA (MBR+DSR-ZTW+RR-ZTMB) had significantly higher Walkley-Black C, KMnO4-C and very labile SOC compared with TPR-CTW in surface (0–15 cm) soil. Interestingly, addition of residues with mixed C:N ratios (legume and rice residues) failed to register improvement in soil mineral N, owing possibly to greater portioning of N towards soil microbial biomass (SMB) and particulate organic matter (POM) associated pools. Fascinating results could be expected in the present experiment with the passage of time.