Search Results

You are looking at 1 - 6 of 6 items for :

  • Author or Editor: A. N. Kishaba x
  • HortScience x
Clear All Modify Search

Abstract

WMR 29 is a productive, watermelon mosaic virus (WMV) 1 resistant muskmelon adapted for desert culture with excellent shipping characters: nearly spherical shape; heavily netted; dry stem scar; firm blossom end; very firm flesh at full slip; bright salmon-orange flesh; high soluble solids; small, dry seed cavity; and pleasant taste and aroma. Watermelon mosaic virus causes severe stunting and malformation of stems and leaves, and yield reduction of muskmelons in the American desert Southwest. WMV 1 and WMV 2 are contributing factors in declining muskmelon acreage in Imperial Valley during the last 40 years. It is common for Imperial Valley fields to be 100% infected by end of harvest. Dominant, single gene resistance to WMV 1 was found in PI 180280 (1). Resistance to WMV 2 has not yet been reported although cultivars appear to vary in field tolerance to WMV 2.

Open Access

Abstract

The melon (or cotton) aphid (Aphis gossypii Glover), an economically important pest throughout the world (1), is an important vector of muskmelon viruses (6), and often causes damage by feeding large populations on this favored host (7). Resistance to the melon aphid was found in muskmelon PI 371795 from India (4).

Open Access

Abstract

When free choice was available in the Geld, build up of melon aphid (Aphis gossypii Glover, Western Biotype) was extremely low on Cucumis melo L. breeding line U 90234 derived from PI 175111, even if it was next to heavily infested suscepts. LJ 90234 infested with large no. of aphids which were given no choice for food survived with little injury while treated susceptible hosts were killed. Melon aphid nymphs confined on young mature leaves of LJ 90234 often died and survivors grew slowly to small body size and their fecundity was reduced. LJ 90234 is attacked by other insects, however. LJ 90234 appears to exhibit nonpreference, apparent tolerance, and apparent antibiosis to the melon aphid.

Open Access

Confined-leaf tests in a greenhouse showed Lagenaria siceraria (Molina) Standley plant introduction (PI) 442369 was as susceptible to sweetpotato whitefly, Bemisia tabaci Gennadius, oviposition as Cucumis melo L., Cucurbita ecuadorensis Cutler and Whitaker, and Cucurbita lundelliana Bailey, whereas L. siceraria accessions PI 419090, PI 419215, PI 432341, and PI 432342 were resistant. Resistance rankings of L. siceraria accessions based on adult counts in greenhouse and field tests were similar. Adult entrapment among trichomes was highest on adaxial leaf surfaces of L. siceraria PI 419090. Abaxial leaf trichome density was 48.7/mm on sweetpotato whitefly-resistant L. siceraria PI 432342, 42.1/mm2 on Cucurbita lundelliana PI 540895, and ranged from 51.0 to 85.5/mm2 on Cucurbita ecuadorensis PI 540896. Leaf trichome densities of selected plants of four L. siceraria accessions ranged from 33.0 to 52/mm2 on the abaxial and from 6.3 to 20.8/mm2 on the adaxial surface. Scanning electron micrographs of the abaxial leaf surface, the preferred surface for oviposition, suggest that trichome configuration (density and arrangement of different lengths) could be a factor in reduction of whitefly oviposition on L. siceraria.

Free access

Abstract

Greenhouse and field tests showed casaba melon, (Cucumis melo L. cv. Deserta Naja) to be highly susceptible to the western spotted cucumber beetle (Diabrotica undecimpunctata ssp. undecimpunctata Mannerheim). F1 and F2 progenies derived from a cross between ‘Deserta Naja’ and a comparatively resistant melon aphid-resistant breeding line ‘Top-Mark’ were nearly as susceptible as ‘Deserta Naja’, indicating a dominance of susceptibility. The mean damage to the progeny was significantly different from that of ‘Deserta Naja’; however, this indicated that dominance was incomplete. Greater numbers of the beetles on ‘Deserta Naja’ than on other entries in a field trial indicated that preference is associated with its high susceptibility. Differential damage to ‘Top-Mark’ in free-choice and no-choice tests supported the theory that resistance includes non-preference.

Open Access

Abstract

When given a choice, the cabbage looper, Trichoplusia ni (Hübner), preferred lettuce for oviposition over chard [Beta vulgaris L. (Cicla group)], cabbage [Brassica oleracea (Capitata group)], broccoli (Brassica oleracea L. [Italica group)], and spinach (Spinacia oleracea L.). Preference did not appear to be related to leaf area or to any factor that enhances the survival of progeny of a particular plant species. A 20- to 29-fold difference in oviposition was noted on lettuce grown under 2 environmental conditions.

Open Access