Study on the seed and fruit characteristics of 17 Pinus koraiensis clones
Pinus koraiensis is a precious timber and nut tree species in Northeast China.In order to screen out the Pinus koraiensis clones with excellent fruit in Liaoning,17 Pinus koraiensis clones were used as test materials,and multiple traits of cones(cone length,cone width,cone weight,etc.)and seed indexes(seed length,seed width,weight of 1000-grain seeds,kernel length,kernel width and weight of 1000-grain kernels)were selected.As the basis for screening,the clones were ranked and evaluated by principal component analysis,membership function method and Brepin multi-trait comprehensive evaluation method.The results showed that there were significant(P<0.05)or extremely significant(P<0.01)difference among different clones in cone and seed traits,such as number of cones per plant,weight of cones per plant,number of seeds per cone,weight of a single cone,length of the cones,length of the seeds,width of the seeds,weight of 1000-grain seeds,kernel length,kernel width and weight of 1000-grain kernels.Moreover,the repetition power of these indicators is more than 70%,which provides the possibility for the breeding of excellent clones of Pinus koraiensis.Among the three evaluation methods,Da 748 and 81019 performed outstandingly,and their mean values of cones per plant,seeds per cone,weight per cone,1000-seed weight of seeds,1000-grain weight of kernels and total mass per cone were 9 and 9,70 and 57,127.62 g and 161.53 g,906.67 g and 1 070 g,333.33 g and 400 g,4.8 kg and 1.45 kg,respectively.Da 748 had a high yield per plant,which was 2.68 times of the average value of the tested clones,while the cones and seeds of 81019 were large,and the weight of single cones,weight of 1000-grain seeds and weight of 1000-grain kernel were 1.22 times,1.35 times and 1.36 times that of the tested clones,respectively.This results have important guiding significance for the development of Pinus koraiensis industry in Liaoning.