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Black rot caused by Xanthomonas campestris pv. campestris (Xcc) is a very important disease of cauliflower (Brassica oleracea botrytis group) resulting into 10–50% yield losses every year. Since there is a dearth of availability of resistance to black rot disease in B. oleracea (C genome), therefore exploration of A and B genomes was inevitable as they have been reported to be potential reservoirs of gene(s) for resistance to black rot. To utilize these sources, interspecific hybrid and backcross progeny (B1) were generated between cauliflower “Pusa Sharad” and Ethiopian mustard “NPC-9” employing in vitro embryo rescue technique. Direct ovule culture method was better than siliqua culture under different temperature regime periods. Hybridity testing of F1 inter-specific plants was carried out using co-dominant SSR marker and Brassica B and C genome-specific (DB and DC) primers. Meiosis in the di-genomic (BCC) interspecific hybrid of B. oleracea botrytis group (2n = 18, CC) × B. carinata (2n = 4x = 34, BBCC) was higly disorganized and cytological analysis of pollen mother cells revealed chromosomes 2n = 26 at metaphase-I. Fertile giant pollen grain formation was observed frequently in interspecific F1 hybrid and BC1 plants. The F1 inter-specific plants were found to be resistant to Xcc race 1. Segregation distortion was observed in BC1 generation for black rot resistance and different morphological traits. The At1g70610 marker analysis confirmed successful introgression of black rot resistance in interspecific BC1 population. This effort will go a long way in pyramiding gene(s) for resistance against black rot in Cole crops, especially cauliflower and cabbage for developing durable resistance, thus minimize dependency on bactericides.

Results of a field experiment conducted during the rabi season 2018-19 to determine the residue dynamics of three newer insecticides on cabbage, variety Pusa Cabbage-1, are reported. The average recovery values were calculated to be 88.97, 84.46 and 81.58 per cent, respectively for diafenthiuron, indoxacarb and novaluron. Novaluron showed minimum initial deposit of 0.218 mg kg-1, followed by diafenthiuron (0.309 mg kg-1) and indoxacarb (0.604 mg kg-1) which were below their respective MRLs on cabbage. All the three insecticides were below their quantification limits on 7th d after spray. The limits of quantification by HPLC for diafenthiuron, indoxacarb and novaluron were 0.0307, 0.0127 and 0.0158 mg kg-1, respectively. The half-life values were 1.05, 1.73 and 1.14 d respectively for diafenthiuron, indoxacarb and novaluron, with their safe waiting periods of 0.77, 0.13 and 1.91 d respectively on cabbage heads. [ABSTRACT FROM AUTHOR]

Investigations were carried out during two consecutive Rabi seasons of 2014 and 2015 at the Experimental Farm of the Department of Seed Science and Technology, Dr Y S Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, India to study the spatial distribution of Brevicoryne brassicae in cabbage. One month old cabbage seedlings were planted in the field in the month of November during both the years. Distribution pattern of any insect population is an important aspect as it represents the interaction between individuals of the species and their habitat. Spatial distribution is useful for designing efficient sampling programmes for population estimation and development of population models. Spatial distribution is also important to understand the bioecology of the pest and to determine the sampling protocol for that species. In the present study variance to mean ratio (s2/ X),mean crowding (X*), ratio of mean crowding to mean (X*/X), 'k' of negative binomial, Taylor's power equation (s2 = 0.9099X1.55 during 2014 and s2 = 2.9861X1.1949 during 2015), Iwao's patchiness regression and optimum number of samples (Nopt) required to achieve the desired precision were calculated for different densities. Cabbage aphid, B. brassicae appeared in the fourth standard week i.e last week of January( 26.2 aphids/ plant during 2014 and 0.30 aphids/ plant during 2015) and persisted upto thirteenth standard week i.e last week of April ( 18.4 aphids/ plant during 2014 and 18.2 aphids/ plant during 2015) and followed a negative binomial distribution during both years. Optimum number of samples (Nopt) required varied with mean density as well as precision level. The present study will serve as basic information to develop a sampling plan of B. Brassicae in cabbage for its monitoring and management. [ABSTRACT FROM AUTHOR]

The present study screened a large range of cauliflower (Brassica oleracea L. var. botrytis L.) germplasm for resistance to downy mildew [Hyaloperonospora parasitica Constant (Pers.:Fr) Fr.] and observed the progress of the disease in order to design suitable breeding strategies. Pot experiments using artificial inoculation were conducted under a climate favourable to the disease, and the percentage disease index (DI) was measured 10, 20, and 30 d after inoculation (DAI). Of the 190 genotypes screened, seven were highly resistant (1 < DI ≤ 10), 21 were moderately resistant (10 < DI ≤ 25), 51 were moderately susceptible (25 < DI ≤ 50), 95 were susceptible (50 < DI ≤ 75), and 16 were highly susceptible (75 < DI ≤ 100). The seven most resistant genotypes were BR-2, CCm, 3-5-1-1, CCm-6, CCm-5, MGS-2-3, and cc-12. The overall mean DI value increased from 45.2% at 10 DAI to 58.5% at 30 DAI. Among the genotypes screened, the incidence of downy mildew ranged from 4.5 - 84.6% at 10 DAI, 5.5 - 92.0% at 20 DAI, and 6.0 - 98.8% at 30 DAI. Different stages of plant development showed a strong positive correlation for downy mildew reaction in the genotypes tested. Genotypes identified as resistant can be used as donors to develop multiply-resistant varieties of cauliflower. [ABSTRACT FROM AUTHOR]

In a study at the subtropical vegetable-growing areas of the state of Jammu and Kashmir (J&K), a quasi-experimental research design with a non-equivalent control group was employed to examine the impact of an integrated pest management (IPM) program implemented from 2008 to 2010 on the adoption of non-chemical pest management practices, pesticide use by weight (active ingredient [a.i.]), pesticide use frequency, field use environment impact (FEIQ) and safe handling and application of pesticides by IPM-trained farmers. There was no significant change in adoption of non-chemical practices, other than pheromone traps used by okra ( Abelmoschus esculentus (L.) Moench) growers. Growers reduced FEIQ by 17.9 per hectare from 2008 to 2010. Pesticide use (a.i.) did not decrease significantly, and frequency decreased significantly by 72.4% only in cauliflower ( Brassica oleracea L. var. botrytis ). The vegetable growers did not use protective equipment while handling and applying pesticides thus putting themselves at risk. Implementation of IPM thus needs to be reexamined to significantly reduce pesticide use by weight, treatment frequency and FEIQ. [ABSTRACT FROM AUTHOR]