Combining Ability Analysis And Identification Of Resistance To Phytophthora Blight In Pepper

Six pepper bred lines were used as parents to prepare15 hybridsbyGriffing₄complete diallelcrossesand field experiment was done by randomized block design with 3repeats.The combining ability of 11 economic traits was analyzed.The results show that:（1）Foreconomic traitscomparison,671A×716 showed the highest plant height,Meanwhile,671A×716 indicated most number of fruit per plant,longest fruit and highest yield of every plant,678×716 was related to heaviest weight of per fruit.671A×691MB got themost plant width.In view ofnutritional qualities,VCand dry mass showed the highest in the the combination of 671A×678.Highest content ofsoluble sugar and cellulose content were received in the combination of 715×716,The highestsoluble protein contentwas in the combination of678×715.For capsaicin content,678×691MB showed the most.（2）The GCA variance and the variance of specific combining ability were significantly differentamong different parents and among traits.The 678 was suitable for the high yield breedingobjective,678 and 671A were excellent to develop hybrid withhigh VC content andline 691MB and 716 for hybrid with high content of soluble protein and high soluble sugar.（3）Isolation and identification of Phytophthora capsici fungi,The fungus mycelia grew well and fast on the CA medium.At 26℃temperature,the white bacteria and uniform round colonies could form around 3 days on the CA medium,and produced lots of spores and the speed of sporulation was very fast.Spore suspension was inoculated with pepper seedlings.After 10days,the disease was in accordance with the Koch rule,which proved that the isolated fungus was the fungus ofPhytophthora capsici.（4）Twenty one pepper lines or hybridswere inoculated with the method of root irrigation,and the incidence of the disease was investigated after 10days.It was identified that the 691MB×715 combination was moderate resistant,671A×678,671A and 671A×691MB were highest sensitiveto the Phytophthora capsiciand the remaining 17lines or hybridswere susceptible ones.