玉米粉和乳酸菌对甘薯蔓、酒糟及稻草混合青贮品质的影响

为评价玉米粉和乳酸菌对甘薯蔓、酒糟及稻草(4∶4∶2)混合青贮品质的影响,试验设对照组(CK)、玉米粉添加组(CF)、乳酸菌添加组(LAB)、玉米粉和乳酸菌组合添加组(CF+LAB),每个处理6个重复,室温下贮藏60 d开封,取样分析青贮品质。结果表明,添加玉米粉和乳酸菌制剂均明显提高了青贮料的感官品质,与CK相比,CF处理、LAB处理及CF+LAB处理中 CP含量极显著提高(P<0.01), NH₃-N/TN、AA、PA、Ash含量极显著降低(P<0.01),CF处理极显著地提高了DM、CP、LA含量(P<0.01),而LAB处理则极显著地降低了NDF、ADF含量(P<0.01),CF+LAB中NH₃-N/TN、AA含量及pH值极显著低于LAB(P<0.01),显著低于CF(P<0.05)。综上所述,添加玉米粉和乳酸菌制剂均提高了青贮品质,单独添加乳酸菌制剂青贮品质要次于单独添加玉米粉,两者组合添加青贮品质更好。     

Greenhouse gas emissions in response to straw incorporation,water management and their interaction in a paddy field in subtropical central China

A field experiment was conducted to study the effects of combination of straw incorporation and water management on fluxes of CH₄, N₂O and soil heterotrophic respiration (Rh) in a paddy field in subtropical central China by using a static opaque chamber/gas chromatography method. Four treatments were set up: two rice straw incorporation rates at 0 (S1) and 6 (S2) t ha^?1 combined with two water managements of intermittent irrigation (W1, with mid-season drainage) and continuous flooding (W2, without mid-season drainage). The cumulative seasonal CH₄ emissions for the treatments of S1W2, S2W1 and S2W2 increased significantly by 1.84, 5.47 and 6.63 times, respectively, while seasonal N₂O emissions decreased by 0.67, 0.29 and 1.21 times, respectively, as compared to S1W1 treatment. The significant increase in the cumulative Rh for the treatments S1W1, S2W1 and S2W2 were 0.54, 1.35 and 0.52 times, respectively, in comparison with S1W2. On a seasonal basis, both the CO₂-equivalents (CO₂e) and yield-scaled CO₂e (GHGI) of CH₄ and N₂O emissions increased with straw incorporation and continuous flooding, following the order: S2W2>S2W1>S1W2>S1W1. Thus, the practices of in season straw incorporation should be discouraged, while mid-season drainage is recommended in paddy rice production from a point view of reducing greenhouse gas emissions.     

南方水稻区域试验品种对水稻白叶枯病抗性调查

1983-2007年,对南方稻区水稻区域试验品种、组合的白叶枯病抗性进行了研究。结果表明,在1 805个参试品种、组合中,78个表现抗白叶枯病,抗病品种频率为4.3%;其中,常规水稻74个,占抗病品种的94.9%。在1 219个籼型杂交水稻中,抗病的组合3个,中抗的76个,抗病和中抗组合频率分别为0.2%和6.2%。不同类型和不同生态型水稻的抗病品种频率差异显著,晚粳>早籼>中籼>晚籼;常规水稻>杂交水稻。籼型杂交水稻中抗病组合频率为:杂交晚稻>杂交早稻>杂交中稻。1990-2004年,17个抗或中抗白叶枯病的优良水稻新品种、组合通过国家审定。     

Natural hybridization between wheat (Triticum aestivum L.) and its wild relatives Aegilops geniculata Roth and Aegilops triuncialis L.

BACKGROUND

Cultivated bread wheat (Triticum aestivum L.) spontaneously hybridizes with wild/weedy related Aegilops populations, but little is known about the actual rates at which this hybridization occurs under field conditions. It is very important to provide reliable empirical data on this phenomenon in order to assess the potential crop–wild introgression, especially in the context of conducting risk assessments for the commercialization of genetically modified (GM) wheat, as gene flow from wheat to Aegilops species could transfer into the wild species genes coding for traits such as resistance to herbicides, insects, diseases or environmental stresses.

RESULTS

The spontaneous hybridization rates between wheat and A. geniculata and A. triuncialis, which are very abundant in the Mediterranean area, have been estimated for the first time in the northern part of the Meseta Central, the great central plateau which includes the largest area of wheat cultivation in Spain. Hybridization rates averaged 0.12% and 0.008% for A. geniculata and A. triuncialis, respectively. Hybrids were found in 26% of A. geniculata and 5% of A. triuncialis populations, at rates that can be ≤3.6% for A. geniculata and 0.24% for A. triuncialis.

CONCLUSION

The detection of Aegilops spp.–wheat hybrids in Aegilops populations indicates that gene flow can occur, although wheat is considered a crop with a low-to-medium risk for transgene escape. These data on field hybridization rates are essential for GM wheat risk assessment purposes. © 2023 Society of Chemical Industry.     

杂交水稻新组合比较试验初报

为筛选出高产、抗逆性强、生育期适合双季稻区种植的杂交水稻新组合,总结其高产配套的栽培技术措施指导当地农业生产,选择五优308、新两优6380、辐优21、特优165、金福优16共5个杂交水稻新组合进行比较试验。结果表明,五优308的产量最高,比对照金优207增产54.6﹪;其次是新两优6380,比对照增产37.9%;再次是辐优21,比对照增产35.6%;增产均达极显著水平,这3个组合可在柳江县双季稻区推广种植。     

纤维素酶处理荞麦秸秆对其纤维结构和滩羊肉品质的影响

本试验旨在研究荞麦秸秆经不同酶活纤维素酶处理对其发酵前后纤维结构、营养成分、微生物数量以及滩羊肉品质的影响.本试验分为两部分,第1部分为酶处理试验,第2部分为饲养试验.酶处理试验共设计3个组,分别为对照组(未经酶处理的荞麦秸秆),试验I组(纤维素酶I处理的荞麦秸秆),试验Ⅱ组(纤维素酶Ⅱ处理的荞麦秸秆),每组3个重复....     

中越水稻迁飞性害虫稻飞虱、稻纵卷叶螟发生关系分析

中越两国同属东亚季风区,水稻病虫害在发生危害上为一个整体。每年水稻稻飞虱、稻纵卷叶螟(以下简称"两迁"害虫)随着季节和气温变化,在两国间往返迁飞,发生为害,相互影响。研究两国水稻迁飞性害虫发生的关系和影响规律,对于提高监测预警的早期预见性和防控工作的主动性,有效控制其危害具有重要意义。2010年以来,中越两国实施了中越水稻迁飞性害虫监测与防治合作项目,通过连续多年开展交流合作,初步明确了越南"两迁"害虫发生规律。本文简要分析了影响越南"两迁"害虫发生的主要因素,探讨了中越两国水稻"两迁"害虫发生规律的相关性,对提高中国"两迁"害虫中、长期预报能力和综合治理水平发挥了积极作用。     

丙溴磷在稻田中的残留降解行为研究

通过田间试验,研究了丙溴磷在稻田中的残留动态过程,借助气相色谱技术,得到添加回收率为80.1～113.2%,相对标准偏差为2.7～9.4%。丙溴磷在稻田水、土壤及水稻植株中的降解半衰期分别为1.9～2.2d,3.6～4.3d,1.8～2.5d;丙溴磷在稻田水、稻田土壤及水稻植株中的最低检出浓度分别为5.0×10-2mg/L、5×10-2、5.0×10-2mg/kg。     

Susceptibility of wild carrot (Daucus carota ssp. carota) to Sclerotinia sclerotiorum

Sclerotinia soft rot, caused by Sclerotinia sclerotiorum, is a severe disease of cultivated carrots (Daucus carota ssp. sativus) in storage. It is not known whether Sclerotinia soft rot also affects wild carrots (D. carota ssp. carota), which hybridise and exchange genes, among them resistance genes, with the cultivated carrot. We investigated the susceptibility of wild carrots to S. sclerotiorum isolates from cultivated carrot under controlled and outdoor conditions. Inoculated roots from both wild and cultivated plants produced sclerotia and soft rot in a growth chamber test. Two isolates differed significantly in the ability to produce lesions and sclerotia on roots of both wild carrots and cv. Bolero. Flowering stems of wild carrots produced dry, pale lesions after inoculation with the pathogen, and above-ground plant weight was significantly reduced 4 weeks after inoculation in a greenhouse test. Wild and cultivar rosette plants died earlier and fewer plants survived when inoculated with the pathogen under outdoor test conditions. Cultivar plants died earlier than wild plants, but survived as frequently. Plants inoculated in the crown died earlier and at a lower frequency than plants inoculated on leaves. Wild carrots may thus serve as a host of S. sclerotiorum and thus eventually benefit from any uptake of resistance genes, among them transgenes, via introgression from cultivated carrots.     

三种抗旱措施对油桃物候期及土壤物理性质的影响

以6 a生曙光油桃为材料,研究了黑膜覆盖、秸秆覆盖和保水剂对油桃物候期及土壤物理性质的影响。结果表明:在油桃生长发育期内,黑膜覆盖与保水剂能有效提高树盘土壤20 cm深处的地温,并使果实着色始期、成熟期较对照提前2~4 d;各抗旱措施均能很好地保持树盘土壤0~20 cm(上层)2、0~40 cm(下层)的水分含量,其中以保水剂效果最显著;保水剂在降低树盘上、下层土壤容重上的作用较其它措施大,可使果实成熟期树盘上、下层土壤总孔隙度比对照分别提高12.62%和4.69%。