Isolated Microspore Culture and Plant Regeneration of Leaf Mustard(Brassica juncea(L.)Czern.et Coss.)

Isolated micmspore culture was carried out with Brassica juncea to study the effects of sterilization methods, culture period of embryos, hormone formula and the concentration of aetivatod carbon on embryogenesis, and the concentration of NAA on induction of roots. The results showed that the embryogenesis on medi- um subjected to filter sterilization is better than medium subjected to autoclaved sterilization. The embryos cultured for 15 d had the highest plantlat regenexafion rate （52%）. NLN-13 liquid medium including 0. 1mg/L 6-BA and 0.2 g/L activated carbon significantly improved the planflet regeneration rate. 1/2 MS inclu- ding 0.3 mg/L NAA had the highest plantlet regeneration rate （ 100% ）. Key words Brassica juncea ; Isolated micmspore culture ; Embryogenesis ; Planflet regeneration

A Method for Preparing Insecticide of Cabbage Worm Pieris rapae and Its Control Effects

[Objective]The paper was to study the field control effects of different formulae of plant extracts against cabbage worm Pieris rapae,and to provide a basis for promotion and application of insecticides in production.[Method]With the leaching solution of radix anemones rivularis,Artemisia carvifolia and Nicotiana rustica,and lime and salt water as the materials,field efficacy test was conducted for consecutive two years.[Method]When the mass ratios of radix anemones rivularis mother liquid,A.carvifolia mother liquid,N.rustica mother liquid,lime water and salt water were 4:2:2:1:1:6,4:2:0:1:1:8,4:0:2:1:1:8 and 0:4:2:1:1:8,the control effects were 82.7%-89.8%,38.3%-42.0%,41.0%-45.4%and 52.9%-56.4%,respectively.The insecticide showed the best control effect when the mass ratio of radix anemones rivularis mother liquid,A.carvifolia mother liquid,N.rustica mother liquid,lime water and salt water was 4:2:2:1:1:6.[Conclusion]The optimal formula has good control effect against P.rapae,and the technology has obtained national invention patent.

Identifying Cytoplasmic Male Sterile Types of Chinese Cabbage(Brassica campestris L.)by Molecular Markers

Different sterile cytoplasm types of nine cabbage cytoplasmic male sterile materials were identified by molecular marker in the study, in order to better use molecular marker to conduct the assisted breeding in the future. Genomic DNA was isolated from Chinese cabbage by CTAB method. The design of two pairs of specific primers was performed on conserved flanking region of orf138 gene in the GenBank. PCR was performed with genomic DNA of the nine Chinese cabbage materials. The bands were sequenced. The homologous comparison was conducted in NCBI, and finally, the type of sterile cytoplasm was determined. The results showed that the bands were amplified only in four Chinese cabbage male sterile materials with two pairs of specific primers PUPIl and PIII/PIV, while the other five materials did not obtain the relative bands. The result was consistent with the field sterility identification. And then four molecular markers of Chinese cabbage Ogura cytoplasmic male sterility （CMS） were obtained. After conducting a homologous comparative analysis with BLAST in GenBank, it was found that the homologous degree was 100% in specific segments of tbe tbree sterility materials （L1-CI, L3-CI and L3- F1 ） and Ogu orf138 gene （GenBank accession No. ： HQ149728） of the reported broccoli Ogu CMS. The homologous degree of L1-F1 was 99% with a variation point. The type of cytoplasmic male sterility of the other five materials needed further research. Four materials of the nine were identified as the radish cytoplasmic male sterility materials and four molecular markers were obtained.

Effects of Different Combinations of Fertilization and Agrochemical Application on Yield and Cost-effectiveness of Cucumber

This study was conducted to provide reference for rational fertilization and agrochemical application in cucumber plantation,and relieve the problem of environmental pollution and vegetable agrochemical residues. The effects of different combinations of fertilization and agrochemical application on cucumber yield and cost input were investigated. Four treatments were conducted,including T1（ conventional fertilization ＋ conventional agrochemical application,CK）,T2（ conventional fertilization ＋ recommended agrochemical application）,T3（ recommended fertilization ＋ conventional agrochemical application） and T4（ recommended fertilization ＋ recommended agrochemical application）. The results showed that T4 had fewer kinds of fertilizers and agrochemicals than that of T1,and had a yield increasing effect on cucumber,and the yield increase was 7 003. 5 kg/hm^2,with an increasing rate of 19. 25%; and it also had obvious cost-saving and benefit-increasing effects,specifically,the cost was saved by 10 941 yuan/hm^2 and the benefit was increased by 31 951. 5 yuan/hm^2. The results of this experiment were satisfactory,and higher benefit was obtained with lower input. This study will provide reference for cucumber planter to choose fertilizers and agrochemicals,and lays a foundation for alleviating the ecological soil problems.

Inheritance of Clubroot Resistance of Miniature Chinese Baby Cabbage and Molecular Markers-assisted Selection

[Objective] The paper was to analyze the inheritance of clubroot resistance of miniature Chinese baby cabbage,to shorten identification time and to improve breeding efficacy of new disease-resistant varieties. [Method] Taking clubroot-resistant Chinese cabbage CCR001,disease-susceptible baby cabbage CM002,and their F_1,F_2 and BC_1 offspring as the research objects,the inheritance of clubroot resistance of baby cabbage was studied. [Result]The clubroot-resistance of baby cabbage was controlled by a single dominant gene,which conformed to Mendel＇s Laws of inheritance. The molecular markers-assisted selection combing with bacterial soil inoculation confirmed that the disease-resistance indeed passed on from the parents,and was inherited in F_1 and F_2. [Conclusion]It is feasible to breed clubroot-resistant baby cabbage by using molecular markers-assisted selection.