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Abstract
Fruits of the firm cultivars ‘Florida MH-1’ and ‘Flora-Dade’ and the less firm cultivar ‘Walter’ tomato (Lycopersicon esculentum Mill.) were harvested at the mature green stage of maturity and held at 20°C. After ripening at 20°C for 7, 14, and 21 days, ‘Florida MH-1’ and ‘Flora-Dade’ fruits were firmer than ‘Walter’ fruits. ‘Flora-Dade’ fruit were as firm at 21 days as fruit of ‘Walter’ at 7 days. ‘Florida MH-1’ fruit were as firm at 14 days as those of ‘Walter’ at 7 days. There was no relation between fruit color and firmness. A seasonal effect on firmness at 7 days was found for ‘Walter’ and ‘Florida MH-1’ but not for ‘Flora-Dade’.
Abstract
The outer pericarp thickness of fruit of tomato (Lycopersicon esculentum Mill) ripened off the vine depended upon the maturity of the fruit when harvested. Immature fruit has thinner outer pericarps than fully mature green fruit. Similar results were obtained with 4 cultivars and 3 fruit sizes. The pericarp thickness did not change during a 6-day ripening period for any maturity. There was no difference in number of cells in the outer pericarp due to maturity or fruit size.
Abstract
The effects of 5-methyl-7-chloro-4-ethoxycarbonylmethoxy-2, 1, 3-benzothiadiazole (MCEB), a proposed inhibitor of ethylene action, and (2-chloroethyl) phosphonic acid (ethephon) on sex expression were observed in androecious and gynoecious phenotypes of cucumber (Cucumis sativus L.) under greenhouse conditions. MCEB had no effect on the androecious phenotype while ethephon (50 ppm) induced pistillate flowers. The effect of MCEB and ethephon treatment was a marked reduction in the number of ethylene-induced pistillate flowers except when there was a 48-hour period between applications of ethephon and MCEB. In the gynoecious phenotype, MCEB (75 ppm) induced staminate flowers, ethephon had no effect, and the effect of MCEB and ethephon treatment was to induce staminate flowers at relatively high concentrations of MCEB (150 ppm).
Abstract
The mode of inheritance of carboxylation efficiency (CE) of tomato (Lycopersicon esculentum Mill.) was studied using parents, F1, BCP1, BCP2, and F2 progeny from the crosses Ottawa 67 (067) × VF 145-7879 (7879) and 067 × LA959. The inheritance of chlorophyll content was studied with the cross 067 × LA959. The difference in CE between 067 and 7879 is controlled by a single gene with high CE apparently conditioned by the high pigment (hp) gene from 067. The differences in CE and chlorophyll content between 067 and LA959 are under digenic control. The differences appear to be controlled by hp from 067 and lurida (lur) from LA959. A causal relationship between chlorophyll content and CE may not exist, but the evidence presented indicates the two characteristics are closely related.
Abstract
Ethephon applied as a foliar spray caused an androecious (all-male) line of Cucumis sativus L. to produce pistillate flowers analogous to those of monoecious phenotypes. The degree of conversion depended on the concentration of ethephon and stage of growth at the time of application. In the greenhouse, a concentration of 50 ppm applied at the 3- or 4-leaf stage was the best treatment for induction of pistillate flowers without marked inhibition of growth.
Abstract
The relative growth rates for tomato (Lycopersicon esculentum Mill.) genotypes differing in carboxylation efficiency (CE) were similar. Manapal (dg), which had a high CE, had a more rapid vegetative phase growth rate and LA 1098 (low CE) was slower growing. Specific leaf dry weight was greater in high CE genotypes indicating that it may be a useful selection criterion. Leaf thickness was greater in the high CE genotypes (Manapal (dg) and 067) than in the intermediate CE cultivars. Manapal (dg) and 067 (high CE) has much greater percent air space in the palisade tissue and much longer palisade cells than 7879 and VF 36 (intermediate CE). Conversely the number of palisade cells cm−2 was much less in the high CE genotypes. These results indicate that differences in gaseous diffusion potential may in part account for genotypic differences in CE. Differences in CE at 21 and 2% O2 indicated that genotypic differences for photorespiration rate was not an important contributor to the variation in CE.
Abstract
Resistance of Lycopersicon accessions, breeding lines and cultivars to the tomato pinworm, Keiferia lycopersicella (Walsingham), and the vegetable leafminer, Liriomyza sativae Blanchard, was evaluated in 5 field studies. PI 126445 and PI 127826 (L. hirsutum Humb. & Bonpl.) and PI 126449 (L. hirsutum f. glabratum Mull.) demonstrated the highest level of resistance to both insects as measured by the number of L. sativae mines and damage and larvae of K. lycopersicella. Levels of resistance to either insect in L. esculentum Mill, accessions studied appeared intermediate. PI 129230 and PI 140403 (L. esculentum) were moderately resistant to both insects in at least two tests.
Abstract
Florida 1011, an inbred line of tomato (Lycopersicon esculentum Mill.) was developed at the Agricultural Research and Education Center in Homestead and Bradenton in cooperation with the H. J. Heinz Company. The line is designated Florida 1011 in recognition of its Southern Tomato Exchange Program (STEP) designation (3).
Abstract
In field tests, the most effective film mulch in deterring insects and reducing insect damage to fruits was aluminum. The insects affected were aphids, brown stink bugs, aphid parasites, and Diabrotica spp. Mosaic virus diseases were reduced among aluminum-mulched squash (Cucurbita pepo L.) and cucumber (Cucumis sativus L.) plants. Plant growth, flowering, and fruiting were delayed in tomatoes (Lycopersicon esculentum Mill.) and southernpeas (Vigna unguiculata (L.) Walp.).