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  • Author or Editor: M. H. Dickson x
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A temperature sensitive gene in broccoli conditions complete male sterility at temperatures of 24° C day and 17° night. At 17° day and 12° night slight development of abnormal pollen occurs and at 10° the plant is highly male fertile. The gene, designated ms 6, behaves as a recessive and can be distinguished from other stable genetic steriles by temperature manipulation. Under field conditions in New York plants remained sterile from June 15 to the end of September.

Open Access
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A diallel of 8 cultivars of snap beans and all F2’s among them was evaluated for transverse cotyledon cracking, “TVC”. Over-dominance was indicated but also TVC inheritance appeared to be complex. The 3 resistant parents had dominant genes for TVC, and the most susceptible parents recessive genes. Crosses between resistant and susceptible cultivars produced more resistant progeny than from crosses of resistant and intermediate cultivars.

Broad sense heritabilites varied from 37.8% to 57.5%. Narrow sense heritability of 26.9% to 46.6% based on F2 and backcross data were obtained while regression analysis of F5 on F4 indicated narrow sense heritability of 37%. Parental performance could only be identified followingtest crossings and growing out subsequent generations.

Open Access
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Lima beans (Phaseolus lunatus L.) were selected for ability to germinate and grow vigorously under 12°C (12 hours)/10° (12 hours) temperatures; 15° is required for good germination of current cultivars. Seed coat color was not associated with cold germination ability.

Open Access
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Abstract

Quality seed is undamaged, has a high level of germination, and will produce uniform, vigorous seedlings without defects under various environmental conditions.

Open Access
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Abstract

A major cost factor in the production of cauliflower (Brassica oleracea var. botrytis L.) is the need to tie leaves to avoid brown discoloration of the curd due to the peroxidase activation by sunlight (3). Even lines with a good self wrapping character need tieing, as small cracks between the leaves can permit light to reach the curd and result in a discolored patch or streak. The persistent white curd character (2), obtained from PI 183214 from Egypt, eliminates the need to tie leaves to produce a white curd, making cauliflower production simple and relatively inexpensive. NY 7642 is an early, persistent white-type cauliflower, released in Apr. 1984 by the New York State Agricultural Experiment Station.

Open Access
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Commercial F1 hybrids of Brassica oleracea L. are currently produced by using self incompatibility. This system has some disadvantages due to the nature and variation of incompatibility and because much hand pollination work is required to produce selfed seed on the self incompatible parents.

Open Access

Abstract

Inheritance of resistance to Pythium, Fusarium, and Rhizoctonia in snap beans, Phaseolus vulgaris L., was studied for three populations involving a common resistant parent (Cornell 2114-12) and 3 different susceptible parents. Pythium resistance was strongly associated with colored seed but resistance was found in some white seeded segregants and was widely influenced by degree of susceptibility of white seeded parents. In contrast to the widely accepted theory that colored seed and resistance to Rhizoctonia are tightly linked, Rhizoctonia resistance seemed to be independent of seed color. Heritability for Rhizoctonia resistance was 0.75 and 0.65 for broad and 0.32 and 0.29 for narrow sense heritability. Resistance to all three diseases was independent and quantitatively inherited. Correlations for resistance to Pythium and Fusarium in F4 with F3 selections (r = 0.557**) were in line with heritability expectations. In the Rhizoctonia selections, generation to generation correlation was high (r = 90**) among those with the best resistance but only moderate among those with moderate resistance. In view of the low narrow sense heritability, selection for resistance in later rather than earlier generations should be more effective.

Open Access

Abstract

Semi-hard seed (SHS) in beans is defined as dry seed which does not imbibe water during a 24 hour soak, but which will gain moisture rapidly at high relative humidity within 14 days and then germinate normally. The inheritance of SHS was found to involve several genes. Soft seed was incompletely dominant to SHS. Narrow sense heritability ranged from 20 to 50% in populations studied. SHS was associated with excellent seed quality resulting in unusually vigorous seedlings.

Open Access
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Abstract

An analytic procedure using spectrophotometry permitted quantitative estimation of chlorophyll and carotenoids in wax beans. Crosses studied demonstrate a wide range for chlorophyll and carotenoid content, with heritability of about .60 for both pigments. Seed chlorophyll was correlated (r=.54) with pod chlorophyll! content in large pods. The results show it is just as important to select for carotenoid content as for early degradation of the chlorophyll in wax beans.

Open Access
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Abstract

Isogenic white-seeded (WS) lines of common bean (Phaseolus vulgaris L.) were developed from colored seeded (CS) lines by backcrossing and mutagenesis. Each CS line was selected for its specific resistance to Pythium, Fusarium, Rhizoctonia, seed corn maggot, mechanical damage, or cold tolerance. In all instances, the WS lines, with the p gene, were inferior to the CS lines with P.

Open Access