None Of Cultivars Research Articles

Screening of cashew cultivars against the pests of Cashew

Results revealed that, the mean incidence of cashew thrips was varied from 6.17 to 13.59% with a mean damage score of 0.25 to 0.54 on all the stages of nut. None of cultivars were found promising against cashew thrips. The cultivar, Vengurla-5 and Vengurla-1 were less susceptible against the leaf miner, Acrocercops syngramma Meyrick with a 4.38 and 6.54% leaf damage, while, Vengurla-3, Hy-320, Bapatla 10/19 and Vengurla-6 were found highly susceptible. The performance of cultivars against apple and nut borer showed that the Bapatla 3/33 had least (4.50%) apple and nut damage, whereas, higher infestation was observed in Vengurla-6 (20.50%) during fruiting stage of cashew.

Grain damage, viability and weight loss in different barley cultivars due to Sitotroga cerealella (Oliv.) infestation

This study was carried out to see the impact of Angoumois grain moth (AGM) on different cultivars of barley so that we must grow resistant variety of barley or improve those which are susceptible to it. Eggs of Sitotroga cerealella (Oliv.) were collected and reared in incubators available in Stored Product Entomology Laboratory, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, under temperature 27 ± 2°C and 60 ± 2% relative humidity. For the experiment, five different cultivars of barley; Sanober-96, Jau-83, Soorab-96, ICBA and Sterling were selected for AGM feed. After an interval of 30, 60 and 90 days of infestation, percentage damage and weight loss in grains were determined. After carrying out laboratory and field germination tests, viability of different cultivars were checked. Damage was maximum in variety Soorab (99.38%), which becomes susceptible while it was minimum in Sanober-96 (90.62%), which becomes resistant. Weight loss was maximum in variety Soorab (49.71%), which becomes susceptible and was minimum in Sanober-96 (45.32%), which becomes resistant. Damage was positively correlated with weight loss and negatively correlated with seed germination. In germination tests, on filter paper, maximum germination was found in variety Sterling (3%) which becomes resistant and it was minimum in ICBA which becomes susceptible (0%). In sand germination test, maximum seeds germinated in variety Sanober-96 (2%), and minimum seeds germinated in ICBA (0%). By calculating the percentage of losses of different cultivars, it was found that none of cultivars proved itself completely resistant or susceptible.

Reaction of winter wheat cultivars registered in the Czech Republic to common bunt (Tilletia tritici (Bjerk.) Wint. and T. laevis Kühn) and sources of resistance

Thirty-six cultivars described as resistant or partially resistant by various authors were tested for reaction to a mixture of Tilletia tritici (race T-l) and Tilletia laevis (race L-5). No infection was found in cvs. Amigo, Crest, Franklin, Stava and Tjelvar, low infection (0,9–9,1 %) in Cardon, Wasatch, Hildebrands Weissweizen B, Shekhurdinovka, Nebred and Dobrovicka přesivka. In other trials separate inoculation with T tritici and T. laevis was carried out. None of the cultivars registered at present in the Czech Republic and of the advanced lines in the State Varietal Trial was resistant to Tilletia laevis (race L-5); only advanced line HE-3625 was resistant to T tritici (race T-1). None of the foreign cultivars tested in the State Varietal Trial was resistant to T laevis (race L-5); only cvs. Bussard and Euris showed less than 5 % of infection with T. tritici (race T-1). The following were resistant to both inocula: lines/cvs. with resistance genes Bt3, Bt4, Bt5, Bt6, Bt8, Bt9, Bt10, Bt11, Bt12, Bt13 and the sources of resistance PI 560795 SEL.BCO, PI 560841 SEL. WCO, PI 560 841 SEL.BCL. Breeding for resistance to bunt is discussed.

Soft Red Winter Wheat (Triticum aestivum) Cultivar Response to Metribuzin

Greenhouse and field experiments, at two locations in Georgia, evaluated the tolerance of several soft red winter wheat cultivars (Triticum aestivumL.) to postemergence applications of metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one]. In the greenhouse, none of the cultivars growing in pots tolerated a 0.6 kg ai/ha treatment of metribuzin applied at the two-to three-tiller, six- to nine-tiller, or early-stem elongation growth stages. In nutrient culture, ‘McNair 1003’ was more tolerant to a 0.15 μg/ml concentration of metribuzin than other cultivars. Significant injury and yield reductions of wheat cultivars treated in the field with 0.6 and 1.1 kg/ha of metribuzin occurred. Differences between the cultivars were not uniform over all experiments. Increased injury was accompanied by higher rainfall and low temperatures subsequent to application. None of the wheat cultivars evaluated in the field experiments was injured by the 0.3 kg/ha rate of metribuzin. Acceptable selective weed control was obtained with this rate, indicating that metribuzin could be used in these soft red winter wheat cultivars.