A mutant of the tomato (Lycopersicon esculentum Mill. cv. Flora-Dade) was characterized by straight pedicels oriented in an upright position. A genetic study indicated the mutant character was controlled by a single recessive gene, which has been tentatively designated as up-right pedicel (up). The up locus is linked to the jointless pedicel (j-2) character of ‘Flora-Dade’, with a crossover distance of 8.5 units.
NC50-7, ‘Cherokee’ and ‘Mountain Pride’ are mid-season, determinate (sp gene) tomatoes (Lycopersicon esculentum Mill.) developed at the Mountain Horticultural Crops Research Station, Fletcher, N.C. ‘Cherokee’ and ‘Mountain Pride’ are adapted to vine-ripe harvest for local market and shipping. NC507 is useful as a parent in breeding for firmness and crack resistance and, in addition, is the male parent of the F1 hybrid ‘Mountain Pride’.
Early blight, incited by Alternaria solani (Ellis and Martin) Jones and Grout, is a severe foliar disease of tomatoes in western North Carolina. Resistance breeding, initiated in 1976 at the Mountain Horticultural Crops Research and Extension Center, Fletcher, N.C. has resulted in the development of NC EBR-1 and NC EBR-2. Both lines exhibit a moderate level of foliar resistance to early blight.
The heritability of shortened fruit maturation (SFM) period in Cornell 871213-1, an inbred cherry tomato [Lycopersicon esculentum var. cerasiforme (Dunal.) A. Gray] line, was estimated from a greenhouse experiment. Cornell 871213-1 was crossed with the cherry tomato line NC 21C-1. Mean fruit maturation period (FMP) (days from anthesis to the breaker stage of fruit color) was 40.8 days for NC 21C-1 and 32.0 days for Cornell 871213-1. Parental, F1, F2, and backcross generations all differed in mean FMP and yielded, estimates of broad- and narrow-sense SFM heritabilities of 72% and 40%, respectively, on a single-plant basis. A test for midparent heterosis showed significance. Genetic control of SFM was quantitative in nature and highly dominant. A field study of an F2 population developed from the cross Cornell 871213-1 × NC 84173, the latter a large-fruited tomato line (Lycopersicon esculentum Mill.), gave a mean FMP of 48.4 and 31.2 days for NC 84173 and Cornell 871213-1, respectively. The F1 and F2 generations had FMP of 33.1 and 34.7 days, respectively. The parents, F1, and F2 generations all differed in FMP. Parental, F1, and F2 generations yielded an estimate of broad-sense SFM heritability of 64% on a single-plant basis. F3 progenies from selected F2s were grown in a greenhouse, and F3-F2 regression analysis gave a narrow-sense SFM heritability of 39%. Parental means differed from each other and from the F1 and F2 means for period from sowing to anthesis, fruit weight, and locule number. F1 and F2 means did not differ for any trait and were far below the midparent values, approaching Cornell 871213-1 for each trait except for the number of days from sowing to anthesis. Significant correlations existed in the F2 generation between FMP and fruit weight (0.61) and between fruit weight and locule number (0.69). Significant correlations existed between selected F2s and their F3 progeny for FMP (0.53), fruit weight (0.78), and days from sowing to anthesis (0.78). In the F3 generation, a significant correlation occurred between FMP and fruit weight (0.48). F3-F2 regression and realized heritabilities were used as two estimates of narrow-sense heritability (29% and 31%, respectively) for days from sowing to anthesis.
Eight staked, determinate tomato (Lycopersicon esculentum Mill.) cultivars were harvested when green (before breaker stage) or when pink (breaker stage and riper) in two replicated field studies. In general, total yield and average fruit size were reduced when fruit were harvested at the green stage. Harvest maturity had only a small effect on occurrence of most fruit defects, except fruit cracking, which was more severe for pink than for green fruit in the early season experiment. Although total yields for pink harvested fruit were higher than for green harvested fruit in the early season study, the high incidence of fruit crack in pink fruit resulted in similar yields of U.S. combination grade (U.S. no. 1 and U.S. no. 2) fruit for both treatments. Because the largest fruit often bring a premium price, harvesting fruit when pink probably will result in a higher price per kilogram than harvesting fruit when green. Fruit harvested green, however, are generally firmer, more crack resistant, and require fewer harvests than fruit harvested pink.
There is a good market for heirloom tomatoes that, according to many consumers, taste better than regular tomatoes. Unfortunately, most heirloom tomatoes have little disease resistance, tend to crack, are rough in appearance, and are not uniform in size. Randy Gardner recently developed several new indeterminate hybrid tomatoes with the goal of combining the flavor of heirloom tomatoes with the disease resistance, uniform size, and good shipping characteristics of more modern varieties. Two tests, using organic and conventional practices, were conducted in Waynesville, N.C., in which three popular heirloom varieties (German Johnson, Mr. Stripey, and Cherokee Purple) and four late blight resistant hybrids (NC 0455, NC 0571, NC 0576, and NC 05114), replicated four times, were grown using a high trellis system. The highest yields were obtained with German Johnson NC 0455, and NC 0576 in the conventional trial and German Johnson NC 0455, and NC 0571 in the organic trial. Public taste test results revealed that the experimental hybrid cluster type, NC 05114, was ranked by over 82% of the participants as good or excellent. NC 0455 was rated as good or excellent by >83% of the participants, which was better than the popular heirlooms Cherokee Purple and Mr. Stripey. This study demonstrated that the heirloom-type hybrid tomatoes could be successfully grown in organic and conventional systems in Western North Carolina and that two out of the four tested had flavor ratings similar to, or better than, the three heirloom varieties tested.