氮磷及生物菌肥配施对1.5代园樟子松生长和生理特性的影响

为提高樟子松母树的抗逆性和结实量,该研究对1.5代园樟子松母树施用氮磷及生物菌肥,以不施肥为对照,测定母树的生长量和生理指标。结果表明:施肥处理对1.5代园樟子松的胸径和树高生长量均有显著的影响(P<0.05),明显提高了母树的叶绿素、淀粉、可溶性糖和可溶性蛋白含量,降低了相对电导率、丙二醛、游离脯氨酸含量和过氧化氢酶活性,其中每株母树施尿素400 g、过磷酸钙300 g和生物菌肥400 g的促进效果总体明显,因此生产中1.5代园樟子松母树应采取这一施肥配比,促进樟子松的生长发育。

Generation of seed lipoxygenase-free soybean using CRISPR-Cas9

Beany flavor induced by three lipoxygenases(LOXs, including LOX1, LOX2, and LOX3)restricts human consumption of soybean. It is desirable to generate lipoxygenase-free new mutant lines to improve the eating quality of soybean oil and protein products. In this study, a pooled clustered regularly interspaced short palindromic repeats(CRISPR)-CRISPRassociated protein 9(Cas9) strategy targeting three GmLox genes(GmLox1, GmLox2, and GmLox3) was applied and 60 T_0 positive transgenic plants were generated, carrying combinations of sg RNAs and mutations. Among them, GmLox-28 and GmLox-60 were gmlox1 gmlox2 gmlox3 triple mutants and GmLox-40 was a gmlox1 gmlox2 double mutant.Sequencing of T_1 mutant plants derived from GmLox-28, GmLox-60, and GmLox-40 showed that mutation in the GmLox gene was inherited by the next generation. Colorimetric assay revealed that plants carrying different combinations of mutations lost the corresponding lipoxygenase activities. Transgene-free mutants were obtained by screening the T_2 generation of lipoxygenase-free mutant lines(GmLox-28 and GmLox-60). These transgeneand lipoxygenase-free mutants could be used for soybean beany flavor reduction without restriction by regulatory frameworks governing transgenic organisms.

Effects of Seed Viability and Number of Generations on Genetic Integrity of Soybean Germplasm Zhonghuang 18 by AFLP Markers

The seeds of a soybean cultivar Zhonghuang 18 were subjected to accelerated aging for 0(population G_0-1), 112(population G_0-2), 154(population G_0-3) and 196 d(population G_0-4), whose germination percentage was found to be 98.0%, 95.0%, 81.0%, and 79.0%, respectively. Then, the four populations were regenerated twice in the field. The first descendant populations were marked as G_1-1, G_1-2, G_1-3 and G_1-4, and the second were marked as G_2-1, G_2-2, G_2-3 and G_2-4, respectively. The genetic variation between the control population(G_0-1) and the experimental populations was analyzed using 12 AFLP primer combinations. The results showed that there was no significant difference in genetic similarity between the 11 experimental populations and the control population G_0-1. The genetic similarity between population G_2-4 and G_0-1 was still as high as 0.933 3, indicating that the F_2 generation of the population whose germination percentage was only 79.0% still had a high genetic similarity to the control population. The results of t-tests revealed that the populations G_1-1, G_2-1, G_1-2 and G_2-2 showed no significant difference from the control population G_0-1 in effective number of alleles per locus(Ae), genetic diversity index(H) and Shannon's diversity index(I), while these indices of populations G_0-3, G_0-4, G_1-3, G_1-4, G_2-3 and G_2-4 were significantly reduced. χ~2 tests indicated that the populations G_1-1 and G_2-1 showed little difference, and the populations G_0-2, G_0-3, G_0-4, G_1-2, G_1-3, G_1-4, G_2-2, G_2-3, and G_2-4 showed great difference in allele frequency distribution from the control population G_0-1, and the difference was greater when the seed viability was lower. Compared with the control population G_0-1, the number of rare alleles(Nr) of the populations G_0-2, G_1-1, G_2-1, G_1-2 and G_2-2 showed no significant difference, while that of the populations G_0-3, G_0-4, G_1-3, G_1-4, G_2-3 and G_2-4 declined obviously. These results revealed that compared with the control population, the genetic diversity and Nr for the descendant populations of the populations with 98.0% and 95.0% germination percentages did not change significantly, but declined greatly for the descendant populations of the populations with 81.0.% and 79.0% percentages. The results suggested that the decline in seed viability has a greater impact than the number of generations on genetic structure of soybean germplasm. So, it is suggested that soybean seed with an initial germination percentage of 98.0% should be regenerated before its germination percentage declines to 81.0%.

Rapid generation advance(RGA) in chickpea to produce up to seven generations per year and enable speed breeding

This study was aimed at developing a protocol for increasing the number of generation cycles per year in chickpea(Cicer arietinum L.).Six accessions,two each from early(JG 11 and JG 14),medium(ICCV 10 and JG 16),and late(CDC-Frontier and C 235)maturity groups,were used.The experiment was conducted for two years under glasshouse conditions.The photoperiod was extended to induce early flowering and immature seeds were germinated to further reduce generation cycle time.Compared to control,artificial light caused a reduction in flowering time by respectively 8–19,7–16,and 11–27 days in early-,medium-,and late-maturing accessions.The earliest stage of immature seed able to germinate was 20–23 days after anthesis in accessions of different maturity groups.The time period between germination and the earliest stage of immature seed suitable for germination was considered one generation cycle and spanned respectively 43–60,44–64,and 52–79 days in early-,medium-,and late-maturing accessions.However,the late-maturing accession CDCFrontier could not be advanced further after three generation cycles owing to the strong influence of photoperiod and temperature.The mean total number of generations produced per year were respectively 7,6.2,and 6 in early-,medium-,and late-maturing accessions.These results have encouraging implications for breeding programs:rapid progression toward homozygosity,development of mapping populations,and reduction in time,space and resources in cultivar development(speed breeding).

Nanosecond Pulses Generation with Samarium Oxide Film Saturable Absorber

Nanosecond pulse generation is demonstrated in a mode-locked erbium-doped fiber laser(EDFL) utilizing a samarium oxide(Sm2O3) film. The Sm2O3 film exhibits a modulation depth of 33%, which is suitable for modelocking operation. The passively pulsed EDFL operates stably at 1569.8 nm within a pumping power from 109 to 146 m W. The train of generated output pulses has a pulse width of 356 nm repeated at a fundamental frequency of 0.97 MHz. The average output power of 3.91 m W is obtained at a pump power of 146 m W, corresponding to 4.0 nJ pulse energy. The experimental result indicates that the proposed Sm2O3 saturable absorber is viable for the construction of a flexible and reliably stable mode-locked pulsed fiber laser operating in the 1.5 m region.

湿地松1.5代种子园无性系开花物候期的观测

为提高湿地松种子园种子产量和遗传品质,更好地开展人工控制授粉,对江西省峡江县湿地松1.5代种子园内51个无性系的开花物候期进行连续2 a的观察和分析。结果表明,种子园内无性系雄球花物候期可分为花芽期、变色期、膨大期、散粉期以及散粉结束5个时期,其开放过程约为27 d,大部分无性系雄球花于3月中上旬进入散粉期。雌球花物候期可分为花芽期、形成初期、授粉期以及闭合期4个时期,其开放过程约为18 d,大部分无性系雌球花于3月中旬进入授粉期。51个无性系雄球花散粉期平均为9~11 d,雌球花授粉期平均为10 d左右。并且,湿地松1.5代种子园各无性系间雌雄球花花期、同株雌雄球花花期均表现出较大差异性。该结果可为种子园后续的经营管理、人工控制性授粉以及高世代种子园建设等工作提供参考。

兴安落叶松1.5代种子园营建技术研究

兴安落叶松1.5代种子园建园的技术要点,优树来源于收集区最优良的无性系优树;选择适宜的园址,并进行详细规划,为实施建园与生产管理提供科学依据;无性系配置方式采用分组复错位小群团排列法(又称双向逆行网眼式错位法)定植建园后,要进行集约化的经营管理。

长白落叶松1.5代种子园营建技术

永吉县西阳林木种子园2010年开始进行长白落叶松1.5代种子园建设工作,采用先定砧、后嫁接方式建园。建园材料为88个优良无性系。其中,从第一代种子园生产区中逆向选择无性系47个,优良种源天然林优良林分选择无性系41个。建设总面积20 hm^2,区划为4个大区、18个小区,以小区为单位利用完全随机法配置无性系,为充分异型交配创造条件。

Numerical simulation on magnetohydrodynamic power generation channel of scramjet

The reverse magnetohydrodynamic(MHD)energy bypass technology is a promising energy redis⁃tribution technology in the scramjet system,in augmented with a power generation equipment to supply the neces⁃sary long-distance flight airframe power.In this paper,a computational model of the scramjet magnetohydrody⁃namic channel is developed and verified by using the commercial software Fluent.It is found that when the mag⁃netic induction intensity is 1,2,3,4 T,the power generation efficiency is 22.5%,22.3%,22.0%,21.5%,and decreases with the increase of the magnetic induction intensity,and the enthalpy extraction rate is 0.026%,0.1%,0.21%,0.34%,and increases with the increase of the magnetic induction intensity.The deceleration ef⁃fect of electromagnetic action on the airflow in the power channel increases with the increase of magnetic induc⁃tion intensity.The stronger the magnetic field intensity,the more obvious the decreasing effect of fluid Mach num⁃ber in the channel.The power generation efficiency decreases as the magnetic induction intensity increases and the enthalpy extraction rate is reversed.As the local currents gathering at inlet and outlet of the power generation area,total temperature and enthalpy along the flow direction do not vary linearly,and there are maximum and minimum values at inlet and outlet.Increasing the number of electrodes can effectively regulate the percentage of Joule heat dissipation,which can improve the power generation efficiency.

“第一代”和“第二代”之间的年轻澳籍华人——关于自我认同发展的探讨

本文所关注的对象是出生于海外成长于澳洲的、夹杂在第一代和第二代之间的年轻华人移民,即所谓的“generation1.5”。本文从他们到达澳洲时的年龄为依据,将其分为3个类群,分别对他们各自的“自我认同发展”问题作一探讨和思索。

Dual and opposing roles of EIN3 reveal a generation conflict during seed growth

Seed size critically affects grain yield of crops and hence represents a key breeding target.The develop-ment of embryo-nourishing endosperm is a key driver of seed expansion.We here report unexpected dual roles of the transcription factor EIN3 in regulating seed size.These EIN3 functions have remained largely undiscovered because they oppose each other.Capitalizing on the analysis of multiple ethylene biosynthesis mutants,we demonstrate that EIN3 represses endosperm and seed development in a pathway regulated by ethylene.We,in addition,provide evidence that EIN3-mediated synergid nucleus disintegration promotes endosperm expansion.Interestingly,synergid nucleus disintegration is not affected in various ethylene biosynthesis mutants,suggesting that this promoting function of EIN3 is inde-pendent of ethylene.Whereas the growth-inhibitory ethylene-dependent EIN3 action appears to be encoded by sporophytic tissue,the growth-promoting role of EIN3 is induced by fertilization,revealing a generation conflict that converges toward the key signaling component EIN3.

日本落叶松初级种子园半同胞子代的生长特性

利用 2处种子园的 2 0个半同胞种子和 3份CK种子 ,育苗建立试验林。通过对 11年生时的调查材料进行分析 ,结果表明 :①种子园树高比CK优 2 .12 %～ 4.44 %,胸高直径优 2 .2 2 %～ 6 .6 7%,单株材积优 6 .6 7%～ 18.90 %,家系中显著优于CK的系占 15 %～ 2 0 %;②干基弯曲指数 1、2级出现的频率 ,家系比CK多 5 .0 %～ 11.0 %,树干弯曲指数 1、2级家系比CK多 12 %～ 19%;③家系生长的快慢和干曲指数不相关 ;④按 35 %的淘汰率去掉生长不良、干曲指数大的系 ,推算 1.5世代种子园增长率 ,树高是 5 %,胸高直径 8%,单株材积 2 1%,对现有的日本落叶松种子园进行遗传改良 ,应严肃认真地进行子代测定 ,留优去劣 ,提高种子园的遗传品质。

Distribution of the Classification Traits in the F_2 Progeny of Two Crosses of indica/japonica in Rice (Oryza sativa)

Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F_2 progeny of indica-japonica hybrids, 02428/Pei'ai 64 and Taichung 65/Teqing. There existed resemblance normal distribution in plant height, and the distribution had no relationship with the seed setting rate and plant height in F_1 progeny, suggesting that there were no gametic selection for the plant height in the F_2 progeny of indica-japoniea hybrids. An average seed setting rate of the F_2 was equal to the F_1 populations in the recombination of 02428/Pei'ai 64 in which there was an excellent cross compatibility, but the remarkable increase in the seed setting rate from the F_1 to F_2 in Taichung 65/Teqing, indicating that gametic selection only took place in the indica-japonica crosses with low cross compatibility while null or little in the hybrids with high compatibility. There were many intermediate types among the leaf pubescence, color of hull at heading, and length of the first and second panicle internode, and these Cheng's morphological traits was distributed normally; there were also a little intermediate types in hull hairness and phenol reaction with bi-peak distribution; while length to width ratio of grain was inclined to the japonica types obviously showing a skewed distribution in the F2 population. Although Cheng's morphological traits in F_2 populations had inconsistent distribution types, Cheng's morphological traits index showed normal distribution, which suggested that intermediate types, i.e. indicalinous or japonicalinous, were primary in F_2 population.

Genetic Diversity and Mating System Analysis of Pinus massoniana in Second-Generation Clonal Seed Orchard

A total 61 clone parents and 320 open-pollination progenies from 8 clone individuals were identified by 12 polymorphic SSR loci.The result showed that the level of genetic diversity in progeny population was the same as in maternal population, progeny population had all alleles detected in maternal population,and there were not obvious surplus phenomenon of homozygotes in progeny population (F= 0.046).The south crown had more strobili than the north crown,however the genetic diversity of the north crown strobili was not substantially reduced.The progeny of neutral trees had the same level of genetic diversity as in the progeny of partial female trees,with the fixation index tended to be zero,which was accorded with Hardy-Weinberg equilibrium.The multilocus outcrossing rate in the seed orchard was 1.097,and there was no significant inbreeding between parents(t_m-t_s= - 0.031).The multilocus outcrossing rate and singlelocus outcrossing rate in the south crown were higher than that in the north crown.The multilocus outcrossing rate of partial female trees was the same as in neutral trees,and the neutral tree had no obvious declining outcrossing rate with reduced proportion of female and male strobilus compared with partial female tree, with the fixation index tended to be zero.The progeny of the second generation clonal seed orchard still had rich genetic diversity,gene exchange among clones was relatively sufficient,and biparental inbreeding was not significant.