干旱和高温危害毛竹竹笋—幼竹生长初报

1985年4—5月份持续一个多月的高温、干旱,使安吉县毛竹重点产区的新竹眉围下降、产量骤减,残次竹增多,估计共损失竹材120余万支,损失产值200余万元。据我们分析,在毛竹笋期,高温和干旱,尤其是后者是造成竹林减产的主要原因。因此,除了在栽培方面着手研究抗旱保竹的技术措施外,在有条件的地方应发展灌溉,以尽可能减少损失。     

亏缺灌溉对藜麦光合特性、营养品质和产量的影响

针对藜麦生产过程中合理水分管理措施缺乏的现实问题,探索亏缺灌溉对藜麦光合特性、营养品质和产量调节的生理基础,为藜麦节水高产优质栽培提供理论依据和技术支持。以‘青藜2号’为供试材料,通过设置充分灌溉、轻度亏缺灌溉和重度亏缺灌溉3个处理,探索不同灌溉处理对藜麦光合特性,籽粒蛋白质、氨基酸质量分数和产量性状的影响。亏缺灌溉使藜麦植株在不同生育期的P_n、T_r和G_s显著降低,但C_i和叶片水分利用效率(WUE)显著升高,且降、增幅随亏缺灌溉程度的加剧而增大;亏缺灌溉降低了藜麦籽粒的蛋白质质量分数、氨基酸总量和氨基酸各组分质量分数;亏缺灌溉显著降低藜麦的总分枝数、有效分枝数和主穗面积,相比于充分灌溉和重度亏缺灌溉处理,轻度亏缺灌溉可显著提升藜麦的主穗粒质量、单穗粒质量、千粒质量和产量。亏缺灌溉负面影响藜麦植株的光合特性,但有助于提高叶片WUE;亏缺灌溉不利于藜麦籽粒蛋白质、氨基酸和氨基酸各组分质量分数的提高;轻度亏缺灌溉可有效控制和提高藜麦的主穗面积、单穗粒质量、单株粒质量、千粒质量和最终产量;轻度亏缺灌溉在节约水资源和降低生产成本的同时,能显著提高藜麦的产量,且能维持相对较高的籽粒蛋白质和氨基酸质量分数。     

Identification of QTLs for phosphorus utilization efficiency in maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) across P levels

It is necessary to develop maize plants that are productive when grown in phosphorus (P) deficient soils because of the high cost of P supplementation in soils. The shoot phosphorus utilization efficiency, the whole phosphorus utilization efficiency of plant and root/shoot ratio as well as the quantitative trait loci associated with these traits were determined for a F_2:3 population derived from the cross of two contrasting maize (Zea mays L.) genotypes, 082 and Ye107. A total of 241 F_2:3 families were evaluated in replicated trials under deficient and normal phosphorus conditions in 2007 at Southwest University. The genetic map constructed by 275 SSR and 146 AFLP markers spanned 1,681.3 cM in length with an average interval of 3.84 cM between adjacent markers. Phosphorus was determined in harvested plants separated into two portions, roots and shoots with leaves. The sum of the two portions was used as an expression for P in the whole plant. By using composite interval mapping, a total of 5–8 distinct QTLs were identified under deficient and normal phosphorus, respectively. SPUE and WPUE under deficient phosphorus were controlled by one QTL, which was in the interval bnlg1518-bnlg1526 (bins 10.04) on chromosome 10. The loci of QTLs were same for SPUE, WPUE and RSR under normal phosphorus, which were in the interval bnlg1518–bnlg1526 (bins 10.04) and P2M8/a-bnlg1839 (bins10.07) on chromosome 10. Unlike regions conferring phosphorus utilization efficiency and root shoot ratio under normal phosphorus, the region under deficient phosphorus showed that genes controlling phosphorus utilization efficiency or root shoot ratio might be different. These results may be useful to breeding programs in marker assisted selections to identify phosphorus tolerant genotypes. Junyi Chen and Li Xu contributed equally to this work.     

秸秆和地膜覆盖下春玉米农田腾发特征研究

通过大型称重式蒸渗仪和小型蒸发器测定秸秆和地膜覆盖下不同灌水处理春玉米地的腾发量,并结合气象、春玉米叶面积及产量等数据比较不同覆盖方式和灌水处理的优越性。分析了棵间蒸发量与降雨和灌水的脉冲性关系、降雨对腾发总量和参考作物腾发量的影响,得到各处理下不同生育阶段春玉米棵间蒸发占腾发总量的比例为大?小?大,且秸秆覆盖较地膜覆盖减少无效蒸发的作用强,利用不同处理下腾发总量与叶面积指数所呈现的线性函数关系,可求得春玉米各生育阶段的作物系数和全生育期的水分利用效率。结果表明:河西干旱地区适度调亏对水分利用效率影响不大,地膜覆盖下种植春玉米比秸秆覆盖效果好。     

不同低磷胁迫时间对巴西橡胶树幼苗生长及形态特征的影响

[目的]研究磷素缺乏对橡胶树生长及形态特征的影响.[方法]利用橡胶树RRIM600号实生无性系幼苗为材料,通过水培试验,研究不同低磷胁迫时间对巴西橡胶树幼苗生长及形态特征的影响.[结果]不同低磷胁迫处理时间下,橡胶树株高、整株干重、叶干重均显著低于正常供磷,而根干重、主根长、茎粗均与正常供磷无显著差异.叶干物质分配率随着磷水平下降逐渐降低,茎干物质分配率变化趋势不明显,根干物质分配率则随着磷水平下降呈上升趋势.[结论]橡胶树为适应低磷胁迫,其形态特征会发生明显变化.     

赣南脐橙非充分灌溉条件下水分需求规律研究

在大田相对自然状态下,对赣南脐橙进行了不同生长时期的非充分灌溉试验研究,结果表明:土壤水分过高或过低,均不利于赣南脐橙的生长发育及产量和品质的提高;赣南脐橙在萌芽期、枝梢生长期、开花期和果实生长期的最适土壤含水量分别为10.6%、10.6%、7.1%～10.6%和10.6%～14.1%,相当于田间持水量的41.7%、41.7%、28.0%～41.7%和41.7%～55.5%。     

Evaluation of Iron Deficiency Using Reticulocyte Indices in Dogs Enrolled in a Blood Donor Program

Background

People donating blood more than twice annually are at risk of developing iron deficiency. Little is known about the iron status of dogs enrolled in blood donor programs.

Hypothesis

Dogs donating blood ≥6 times annually will show evidence of iron deficiency based on their reticulocyte indices.

Animals

Thirteen dogs enrolled in a blood donor program donating ≥6 times over the preceding 12 months and 20 healthy nondonor control dogs.

Methods

Prospective observational study. Mature red blood cell (RBC) indices, reticulocyte indices, serum iron, serum ferritin, and total iron‐binding capacity (TIBC) were compared between groups.

Results

Packed cell volume (median 47%, range 40–52%, P < .01), hematocrit (median 46.4%, range 40.3–52.5%, P < .01), and reticulocyte count (median 16,000/μL, range 9,000–38,000/μL, P < .01) were significantly lower in the blood donor dogs. No statistically significant differences were noted in the mature RBC indices between groups. Both reticulocyte mean corpuscular volume (median 88.8 fL, range 83.4–95.5 fL, P = .03) and reticulocyte hemoglobin content (median 24.6 pg, range 23.1–26.6 pg, P < .01) were significantly lower in the blood donor group. Serum iron and ferritin were similar between groups; however, TIBC was significantly higher in the control group (median 403 μg/dL, range 225–493 μg/dL, P = .02).

Conclusions

The findings in dogs donating ≥6 times annually suggest the presence of iron‐deficient erythropoiesis in this population.     

The conservation status of decapod crustaceans in the Western Ghats of India: an exceptional region of freshwater biodiversity

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Factors of species-specific detectability in conservation assessments of poorly studied taxa: The case of polypore fungi

The differing detectability of species is an important issue in conservation assessments, notably for interpreting the heterogeneous datasets of species-rich, poorly-studied species groups. However, detectability has not been explicitly considered in such cases so far. The aim of this study was to extract the main factors of detectability for polypore fungi. I explored interspecific variation in the number of fruit-body records in Estonia (13 210 records of 212 species) in relation to five potential factors of their detectability: longevity, size, bright colour, typical microhabitat and field identificability. The longevity and identificability of fruit-bodies emerged as major factors, with their extreme combinations revealing a variation of over two orders of magnitude in the number of records. The possibility that these factors are related to true abundances in the field cannot be rejected, but it is unlikely. The approach enables us to formally distinguish rarely observed but poorly detectable species that should be classified as Data Deficient in the red-listing process; it can also be used for recognizing well detectable indicator and focal species for conservation management.     

区域气象观测站观测资料传输质量分析

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