| Tomatoes have the advantages of rich nutrition, wide adaptability, easy cultivation, high output, versatility and so on, as a result, tomato is an important vegetable in the world. It is also one of the main vegetables in our country. The protectorate cultivation of tomato accounted for about 40% of cultivation of vegetable protected area.Occupy the main position in crop adjustment of agricultural production. Different phase ripe tomato varieties breeding, realize the early, middle and late varieties is tie-in, can extend the supply of tomatoes, which is of great importance. Cultivating new early maturity tomato varieties are especially significant. Because not only can tomato early maturity varieties listed earlier, adjust the off-season supplies, but also can increase the income of producers, in north China, the spring vegetables lack, therefore, pay paticular attention on breeding early maturity varieties. Tomato precocious includes two aspects of mature early and early high yield. In north China, having a high output of early maturity period is more important than early mature. The production og tomato fruit in the first and the second inflorescence quarter has a significant position in total tomato production. Some varieties of the first and second inflorescence fruit production accounts for 30-50% of total output. So, according to the market demand, it is necessary to breed the new tomato varieties of early maturity and early high yield.Tomato maturity period as quality, production and resistance are quantitative traits. They are controlled by multiple genes and their genetic laws are very complicated. In this experiment, 259 F2 plants which were developed from an intraspecific cross between early-maturity tomato 13592 and late-maturity tomato13493 was used to research the genetic laws of mature periods, analyze the correlation of early maturity traits of tomato and analyze QTL mapping. The results are as follows:(1) By analyzing the data of surveyed P1, P2, F1 and F2 generations traits, all the traits associated with early maturity tomato present continuous variation trends, which are typical of the normal distributions. The results show that they are quantitative traits, by multiple control genes.(2) By analyzing the correlation of tomato early maturity traits, the results show that mature stage was significantly positively correlated with first-flowering dates, days of flowering to maturate and days of white-maturate to turning stage, was also positively correlated with days of turning to mature stage, was significantly negative correlated with days of flowering to white-maturate stage. The first-flowering dates was significantly positively correlated with the node of the first flower, in contrast, was significantly negative correlated with days of flowering to maturate and days of flowering to white-maturate stage. Days of flowering to maturate was significantly positively correlated with days of flowering to white-maturate stage, days of white-maturate to turning stage and days of turning to maturate stage. Node of the first flower was significantly positively correlated with early yields and average weight of single fruit. Days of flowering to white-maturate stage was negative correlated with days of white-maturate to turning stage, days of turning to maturate stage and average weight of single fruit. Days of white-maturate to turning stage was significantly negative correlated with days of turning to maturate stage, was significantly positively correlated with average weight of single fruit, was positively correlated with early yields. Days of turning to maturate stage was significantly negative correlated with average weight of single fruit. Early yield was positively correlated with fruit number of early stage and average weight of single fruit. Fruit number of early stage was significantly inversely correlated with average weight of single fruit.( 3) In the study, 312 SSR markers and 256 AFLP markers were used to screen polymorphism. There are 100 polymorphic markers selected, including 37 SSR markers, the percentage of polymorphism is 11.8%, 63 AFLP markers, the percentage of polymorphism was 24.8%.(4) The QTL Ici Mapping3.2 software was used to construct a tomato genetic linkage map. The linkage map had 93 markers, including 7 SSR markers and 63 AFLP markers. The map is the total length of 1353.01 c M, the average distance between markers is 14.55 c M, the maximum genetic distance is 38.02 c M, and the minimum genetic distance is 3.87 c M.The linkage map is composed of 12 linkage groups, the markers uneven distribution in each chain group, the second chain as many as 40 markers in the group.(5) Using QTL Ici Mapping3.2 software, a total of 43 QTLs were detected for the 10 correlation of earliness traits by inclusive composite interval mapping(ICIM), including 6 QTLs for the days of first flowering, 7 QTLs for the first flowering node, 5 QTLs for flowering to white-maturate stage, 14 QTLs for turning to maturate stage and 2 QTLs for average weight of single fruit. In addition, only one QTL was detected for the maturity stage, white-maturate to turning stage and the early yield, 3 QTLs were detected for the days from flowering to maturity and the fruit number of early stage. |
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