A gene flow has been tested from transgenic herbicide-resistant Chinese cabbage to major crops in Cruciferae. Hybridizations were made between transgenic Basta-resistant Chinese cabbage and non-transgenic Chinese cabbage, B. napus, B. juncea and Brassicoraphanus(B. campestris × Raphanus sativus, 2n=4x=38) with honey-bee mediated fertilization. Progeny populations were selected by Basta herbicide. The F1 hybrids with pat gene were again self-pollinated or cross-pollinated with nontransgenic Chinese cabbage and rape naturally or artificially. Pod setting ratio were compared as a tentative parameter for potential gene flow.
Key agronomic characters were compared among the F1 hybrid populations obtained. In the days to flowering after cold treatment, the F1 hybrids of Brassicoraphanus x B. campestris and B. napus x B. campestris(GM) were the shortest (75 days), and the GM Chinese cabbage and the F1 hybrid of B. juncea x B. campestris(GM) were 87 and 93 days, respectively. In the stem length, the F1 hybrid of Brassicoraphanus x B. campestris was the longest(175 cm), and followed by the F1 hybrid of B. napus x B. campestris(GM), the F1 hybrid of B. juncea x B. campestris(GM) in order. The naturally occurring pod setting ratios were fluctuated seriously among individual and segregation lines. Natural pod setting of the transgenic Chinese cabbage was 10 to 19 %. The F1 hybrid of B. napus x B. campestris(GM) showed the ratio of 4-11%. However, the F1 hybrids of B. juncea x B. campestris and Brassicoraphanus x B. campestris(GM) did not produced seeds.
The F1 hybrids with pat gene were hybridized with nontransgenic Chinese cabbage and rape by artificial bud pollination to test potential gene flow. All cross combinations except Brassicoraphanus produced seeds and the pod setting ratios ranged from 35 to 100 percentages.
Thus, the potentials of the gene flow from Chinese cabbage with pat gene to the order specise in the same gene interspecies or intergeneric species and from the F1 hybrids with pat gene to nontransgenic Chinese cabbage and rape were detected. Herbicide resistant test to the acquired seeds by natural and artificial pollinations including honey-bee mediated fertilization using the same materials is going on.
Plant water status during growth is directly and indirectly associated with seed yield. The objective of the present study was to determine the genotypic differences in leaf water characteristics at an early growth stage of soybean [Glycine max (L.) Merrill] plants through the pressure-bomb technique. Measurements of water potential as well as relative water content (RWC) were made at the third leaf from the fully-expanded top leaf of eight different soybean genotypes grown for 31 to 35 days after field emergence. On the basis of the modified exponential model, pressure-volume (PV) curves were fitted well (R2 =0.92** to 0.99** for the curvi-linear region and R=0.67** to 0.96** for the linear region), indicating that a segmented model using PROC NLIN of SAS could be used effectively to estimate the leaf water characteristics. The regression analysis for the pressure-volume (PV) curve revealed genotypic variation in the solute potential at saturation (Ψs,sat :-10.7 to -14.8 bar), solute potential at incipient plasmolysis (Ψs,ip : -14.3 to -18.3 bar), RWC at incipient plasmolysis (RW Cip : 83.3 to 91.7%), high integrated turgor pressure from saturation to plasmolysis ( 1 b : 0.39 to 0.81), and maximum volumetric modulus of elasticity (~varepsilon max : 150 to 445 bar).).