Study On Anther Culture And Pollen Viability Of Different Tomato Varieties

Tomato (Lycopersicon esculentum Mill.), as an important object of vegetable breeding, belongs to Lycopersicon of Solanaceae in botanical classification, which originated from South Ameica and widely distributed in the world with rich nutritious, unique flavor and a wide range of uses. In order to satisfy people’s requirement of the diversity of tomato variety, we must introduce and make full use of tomato germplasm resource with the excellent and special characteristic. In haploid breeding of tomato, haploid can be obtained by anther cultures. Haploid breeding can shorten the breeding cycle and accelerate the breeding rate significantly, Therefore, it’s important to study anther culture of tomato. Another major way to cultivate new varieties of tomatoes is cross breeding. There are many interspecific hybridization experiments with different tomato cultivars, but the embryo abortion appear in hybridization. So the determination of pollen viability and the selection of heat-resistant and hardy varieties is not only a key to the success of hybrid but also a important basis for the selection of pollinated varieties.This test used imported tomato varieties from home and abroad for materials. First of all, different sterilization methods and culture media were adopted in the test. Anther culture were studied on different tomato genotypes. And then, the pollen viability was investigated in31different genotype tomato, and the correlation was analysed between the rate of pollen germination and pollen tube length. Finally, the effects of different culture medias and temperature on pollen viability was studied.1. In order to study the effects of different sterilization time, culture medias and genotypes on anther culture of tomato, the survival rate, contamination rate and callus induction rates of explantes were studied on9kinds of sterilization combination and9kinds of different proportion of incretion using21varieties of tomato introduced as experimental materials. The results show that those anthers achieve higher survival rate and lower comtamination rate which were subjected to a surface treatment with70%ethanol for1second and1%sodium hypochlorite for4minutes. The best media for callus induction in anther is MS+lmg/L6-BA+lmg/LNAA. Genotype had a significant effect on anther culture of tomato, and NT-30has the highest induction rate of anther callus. The results find out the best effect of sterilization combination on bud, and determine the best culture media for anther culture of tomato. It provides an important basis for the effective anther culture of tomato.2. In order to select the suitable measurement methods for pollen viability and make clear the effect of different media form and genetype on pollen viability of tomato, the test choosed4kinds of determination method for pollen vitality and2kinds of media form(solid state and liquid state), and used31varieties of tomato introduced from America as experimental materials. The results show that compared with the staining, the culture method in vitro is more suitable for the determination of pollen viability, and the solid media is better than the liquid media. Various varieties had significant effect on pollen viability, and NT-181has the highest pollen viability. Besides, there is a extremely significant positive correlation with pollen germination rate and pollen tube length.31experimental materials were divided into3catagories by cluster analysis, and NT-163n NT-182、NT-180、NT-186、NT-181had high pollen viability. It provide an important basis for the the variety screening in cross breeding of tomato.3. In order to study the effects of different culture media and temperature on pollen viability of tomato, compare the differences of pollen viability on different tomato varieties, determine suitable culture media and culture temperature for germination of tomato pollen, their pollen germination rate and pollen tube length were studied on5kinds of different culture media and5different culture temperatures using8varieties of tomato introduced from America as experimental materials. The results show that the best medium for pollen germination of tomato is120g/L sucrose+120mg/L boric acid+4mg/L GA3+0.5mg/L thiamine+1%agar. Two-factor variance analysis show that the differences of pollen germination among the different varieties and the different culture temperatures is significant. And the significant interaction was found between them. The optimum temperature for the germination of pollens is25℃. NT-181has the highest pollen viability under25℃. It is concluded that NT-203has the high-temperature resistant ability, while NT-168and NT-186has the low-temperature resistant ability. The results make clear the tolerance of pollen viability of different tomato varieties with different temperatures, which is a basis for the selection of heat-resistant and hardy varieties tomato cultivation.