Stress tolerance in cabbage

B. K. Singh, S. R. Sharma, Chandra Prakash, R. N. Barwal and M. R. Dhiman

ICAR News: A Science and Technology Newsletter 17 (2): 2-3, 2011

E-mail: bksinghkushinagar@yahoo.co.in

            Production of deleterious reactive oxygen species (ROS) such as singlet oxygen (¹O₂), superoxide radical (^●O^-₂), hydrogen peroxide (H₂O₂), hydroxyl ion (OH^-) and free hydroxyl radical (^●OH) is one of the reasons for poor productivity and quality of the harvest under stressful conditions in cabbage. Plants possess well-developed defense systems against deleterious ROSs by limiting their formation and by triggering for their removal. If ROSs are not neutralized, they damage cells, causing susceptibility to biotic and abiotic stresses, yellowing and senescence. Pre-mature senescence leads to loss of vigour, productivity and quality of produce. Antioxidant enzymes- superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT)- have touted as beneficial for mitigating effects of oxidative stresses induced by ROSs. SOD, localized in cytosol, chloroplast, mitochondria and peroxisomes, accelerates the dismutation of ^●O₂^- to H₂O₂. POX, an iron heme protein, catalyses H₂O₂ reduction with a concurrent oxidation of a substrate, mostly located in cell wall, and is involved in the oxidation of phenol compounds towards lignin synthesis. CAT also catalyses H₂O₂ reduction to water and molecular oxygen, and is localized in mitochondria and peroxisomes, and absent in chloroplast. This study determined variability for enzymes SOD, POX and CAT activities, and their inheritance was studied in the cabbage samples harvested at the fresh marketable stage, frozen immediately in liquid nitrogen and placed at -80 ⁰C for assay. Enzymatic antioxidant activities showed 1.6, 12.8, and 18.2-fold difference for SOD, POX and CAT, respectively. Red Cabbage, 83-2, KIRC-1-1, ARU Glory, Kinner Red, MR-1, AC-208, Red Rock Mammoth, KIRC-8 and KIRC-1A showed higher activity of antioxidant enzymes. All enzymatic antioxidants expressed high heritability along with low genetic advance as percentage of mean indicated the predominance of non-additive genes, and provide good prospects for hybridization and hybrid breeding. The results indicate that breeding of antioxidant potential cultivars will enhance the stress tolerance ability of cabbage and will result in healthy plant stand, and thus eventually mitigate climate change effects in cabbage cultivation.

Genetic combining ability for concentration of mineral elements in cabbage head (Brassica oleracea var. capitata L.)

B. K. Singh, S. R. Sharma and B. Singh

Euphytica 184 (2): 265-273, 2012

E-mail: bksinghkushinagar@yahoo.co.in

Abstract

Brassica vegetables are important source of dietary nutrition. However, information on the genetic combining ability of mineral elements such as iron, zinc, copper, manganese, potassium and calcium or their types of genetic effects (i.e. additive or non-additive) is scarce but important as it influences the selection of parents and breeding approaches to be adopted for improvement of nutritional quality of cabbage. Therefore, an attempt was made to estimate combining ability in a line × tester (5 × 11) mating design for minerals. Significant mean square for line × tester interaction was observed for all minerals under study indicating the prevalence of non-additive variance; while less than unity value of σ²_gca /σ²_sca ratio for iron, zinc, manganese, potassium and calcium accumulation indicate predominance of non-additive gene action. The parents 83-2, Pride of Asia, Pusa Mukta, Red Cabbage and MR-1 were found good general combiners for four mineral elements. The general combining ability effects of the parents for various minerals revealed that none of the parents excelled for all the minerals suggesting the need for multiple crossing approaches. The cross 83-1 × AC-1019 (Poor × Poor general combiner) exhibits desirable significant specific combining ability effects for all six minerals might be due to presence of high magnitude of non-additive especially complementary epistatic effects which can be utilize for commercial exploitation of heterosis. This study shows clearly that specific combining ability is more important than general combining ability for predicting hybrid combinations for high mineral content in cabbage head.

Key words: Brassica, micronutrient, macronutrient, human health, biofortification. 

Combining ability for antioxidants and economic traits in cabbage (Brassica oleracea var. capitata L)

B. K. Singh, S. R. Sharma and B. Singh

Indian Journal of Horticulture 68 (4): 490-497, 2012

bksinghkushinagar@yahoo.co.in

ABSTRACT

Fifty-five cross combinations along with their sixteen parents were transplanted in randomized block design to generate information on combining ability of antioxidants and economic traits in cabbage. The significance of mean squares of parents and line x tester interactions revealed the pervasiveness of additive and non-additive variance. Non-additive gene action was found to be predominant for carotenoid content, early maturity, frame spread, gross plant weight, net head weight, core length, harvest index, and head compactness, nevertheless additive genes were responsible for synthesis of ascorbic acid and expression of non-wrapper leaves in desirable direction. Golden Acre was found to be good combiner for seven economically important traits viz., carotenoid, earliness, net head weight, number of non-wrapper leaves, polar and equatorial diameter, and core length. Among 55 cross combinations, Pride of Asia × Red Cabbage, CMS-GA × AC-1019, CMS-GA × EC-490192, and Golden Acre × AC-1021 were most outstanding as indicated by respective high SCA effect. Majority of the cross combinations exhibited desirable SCA effects for various traits and involved at least one of the parents as poor general combiner, which signifies the greater importance of SCA than GCA in predicting hybrid combinations for desirable traits and scope for heterosis breeding for improving the traits of nutrition and economic importance.

Key-words: Carotenoid, ascorbic acid, cabbage, nutrition, GCA, SCA.

Purple-podded French bean with high antioxidant content

B. K. Singh, K. A. Pathak, Y. Ramakrishna, V. K. Verma and B. C. Deka

ICAR News: A Science and Technology Newsletter 17 (3): 9, 2011
E-mail: bksinghkushinagar@yahoo.co.in

A unique French bean line (MZFB 44, IC-0595238) having attractive and colourful purple pods, might be mutant, has been collected from Sherkhan, Kolasib, Mizoram. Unlike green-podded genotypes, the line has dark purple flowers, purple pedicels and petioles, and also purplish leaf venation. The pods are green for first 6-8 days, and then turn completely purple in the next 8-10 days. Immature, tender and fresh pods are rich in anthocyanin content (7.08 mg/ 100 g fresh weight); 16 times higher than the normal green-podded genotypes. This pole-type purple-podded line flowers at 35-40 days after sowing (DAS) and pods are ready for first harvest at around 60-65 DAS with a crop duration of 95-105 days. On an average, the weight and the length of each tender pod are 16.5 g and 17.1 cm, respectively; containing approximately 8.1 seeds. Seeds are kidney-shaped, light brown and 100 seeds weigh approximately 25.0 g. The line bears 10-12 pods/ plant and yields 170-185 g fresh pods/ plant in a total of 6-7 pickings during the rainy season (April-July). On an average, 5-6 seeds are sown in each hill at a spacing of 60 cm × 75 cm during 2^nd week of April, and vine is supported on bamboo-sticks or dried branches. The yield potential (tender pods) of MZFB 44 is 13.5-15.0 tonnes/ ha. Other than being high yield potential and health benefits, the line has ability to penetrate Metro markets, especially hotels, for decorating salad and food items.

                               Purple-podded French bean line (MZFB 44, IC-0595238) 

Effects of vermicompost, fertilizer and mulch on plant growth, nodulation and pod yield of French bean (Phaseolus vulgaris L.)

B.K. Singh, K.A. Pathak, A.K. Verma, V.K. Verma and B.C. Deka

Vegetable Crops Research Bulletin 74: 153-165, 2011

E-mail: bksinghkushinagar@yahoo.co.in

Abstract

Integration of vermicompost and organic mulch as elements of vegetable production system sustain soil fertility and crop productivity. A field experiment was conducted with the objective to investigate the effects of vermicompost, NPK fertilizer and organic mulch on crop growth, nodulation and pod yield of French bean (Phaseolus vulgaris L) with an ultimate aim of optimizing water and nutrient requirement in mild-tropical climate during dry season. The shoot growth traits, namely shoot length, number of primary branches, shoot fresh weight and shoot dry weight were increased by 28-63 % through application of N P₂O₅ K₂O 8:13:10 kg/ha + vermicompost 3.75 t/ha and by 5-50 % in organic mulching treatments. Application of vermicompost reduced nodule fresh weight and nodule dry weight by 44.9 and 44.5 %, respectively. Likewise, corresponding nodule number, nodule fresh weight and nodule dry weight were reduced by 8.6, 11.1 and 14.1 % with organic mulching. Poor nodulations might be due to reduced oxygenation of the soils under vermicompost and organic mulch which is ultimately impeding the nitrogenase activity and biological nitrogen fixation. Mulching of French bean with dried grasses and crop residues are also led to higher single pod weight, pod length, pod weight/ plant and pod yield by 10.9, 12.8, 20.1 and 20.2 %, respectively. Present study shows that application of N P₂O₅ K₂O fertilizer 8-15:13-25:10-20 kg/ha, vermicompost 2.50-3.75 t/ha, 4 cm thick mulch of dried crop residues and 50 % irrigation is the most suitable and sustainable strategy to improve plant growth, pod formation and pod yield of French bean, and soil health of mild-tropical climate during dry season. 

Key words: French bean (Phaseolus vulgaris), mulching, vermicompost, nodulation, pod yield, split plot design (SPD).

Gene action of economic traits in brinjal (Solanum melongena L.)

V Prasad, V K Dwivedi, A A Deshpande and B K Singh

Vegetable Science 37 (1): 97-99, 2010

 Twenty eight cross combinations along with their eight parents were transplanted in randomized block design to generate information on genetic architecture of economic traits in brinjal. The significance of additive and dominance genetic variance suggested that both these gene actions were important in the expression of characters. Dominance genetic variance was greater than additive genetic variance for all traits except fruit length, fruit breadth and average fruit weight, which could be exploited through heterosis breeding, nevertheless fruit size and weight could be improved through hybridization followed by selection. The positive sign of F and more than one value of KD/ KR ratio for plant height at last picking, number of primary branches per plant, days to first fruit picking, fruit setting flowers, fruit length, fruit breadth, yield of marketable fruits per plant and average fruit weight suggested the greater scope of improvement through heterosis breeding.

Key words: Diallel, genetic component, eggplant and quantitative traits. 

Variability and character association in elephant foot yam [Amarphophallus paeoniifoliusm (Dennst) Nicolson].

S Kumar, P K Singh, K Kumar and B K Singh

Journal of Root Crops 36 (1): 105-110, 2010.

ABSTRACT

Analysis of eleven horticultural and quality traits among 35 collections of elephant foot yam revealed the presence of adequate variability which could be harnessed for developing cultivars with high yield potential. Based on individual corm weight, corm yield, dry matter and starch content the following collection such as NDA-35, NDA-9, NDA-5, NDA-14, NDA-4 and NDA-10 were identified as promising for cultivation. The phenotypic and genotypic coefficients of variation were high for number of cormel, weight of individual corm, yield, size of cormel and size of individual corm. Moderate to high heritability was evident for all the traits and was accompanied with high genetic advance for weight of individual corm, size of cormel, yield, size of individual corm, number of cormel which suggests the role of additive gene action and thus a high genetic gain is expected from selection of these traits. Moreover, high heritability along with moderate genetic advance for starch content, plant height, canopy spread and stem girth reveals the presence of additive and non-additive gene action simultaneously. The starch content, plant height, weight of individual corm, size of individual corm, stem girth, canopy spread and dry matter were the most important yield contributing traits based on correlation study. Among them, dry matter, starch content, size of individual corm and plant height showed major effect upon yield as a consequence of direct effect and provides most effective selection indices for improvement of elephant foot yam.

Keywords: Elephant foot yam, variability, heritability, correlation and path coefficient.