Acid detergent lignin,lodging resistance index,and expression of the caffeic acid O-methyltransferase gene in brown midrib-12 sudangrass

Understanding the relationship between acid detergent lignin (ADL) and lodging resistance index (LRI) is essential for breeding new varieties of brown midrib (bmr) sudangrass (Sorghum sudanense (Piper) Stapf.). In this study, bmr-12 near isogenic lines and their wild-types obtained by back cross breeding were used to compare relevant forage yield and quality traits, and to analyze expression of the caffeic acid O-methyltransferase (COMT) gene using quantitative real time-PCR. The research showed that the mean ADL content of bmr-12 mutants (20.94 g kg⁻¹) was significantly (P < 0.05) lower than measured in N-12 lines (43.45 g kg⁻¹), whereas the LRI of bmr-12 mutants (0.29) was significantly (P < 0.05) higher than in N-12 lines (0.22). There was no significant correlation between the two indexes in bmr-12 materials (r = −0.44, P > 0.05). Sequence comparison of the COMT gene revealed two point mutations present in bmr-12 but not in the wild-type, the second mutation changed amino acid 129 of the protein from Gln (CAG) to a stop codon (UAG). The relative expression level of COMT gene was significantly reduced, which likely led to the decreased ADL content observed in the bmr-12 mutant.     

杀菌剂拌种对紫花苜蓿,苏丹草不同活力种批出苗的影响

在４０％土壤饱和持水量和最适萌发温度下，研究了甲基托布津、甲霜灵、杀毒矾和福美双等杀菌剂拌种对紫花苜蓿和苏丹草出苗的影响；进而探讨了不同活力的供试种种批对杀毒矾拌种的反应。４种参试杀菌剂以杀毒矾效果最好，与对照比，其可使紫花苜蓿和苏丹草的存苗率分别提高１４１．９％和３７．７％（Ｐ＜０．０５），使紫花苜蓿死苗率降低８０．８％（Ｐ＜０．０５）。其他３种杀菌剂亦可显著（Ｐ＜０．０５）提高紫花苜蓿种子的存苗率和降低死苗率，提高存苗率的效果依次为甲霜灵（１０９．７％）、甲基托布津（８３．９％）和福美双（４８．４％），但对苏丹草种子作用不显著。杀毒矾处理对中活力和高活力紫花苜蓿种子较低活力种子更为明显、有效，与对照比，中活力和高活力种批的存苗率分别提高了１１１．５％和１００．０％，而低活力种批仅提高了３１．０％。但杀毒矾对苏丹草不同活力种批的作用效果不显著。     

高丹草生长动态及收割期的研究

对高丹草不同生长阶段的株高、生长速度、物质积累动态及产量组成进行了研究,并对其营养价值进行评定.结果表明,旱作条件下,高丹草株高、生长速度、产草量及茎/叶变化动态符合Logistic模型,苗期生长缓慢,拔节期生长最快,拔节期过后生长速度减缓,表明拔节期是营养体产量形成的关键时期.干/鲜及营养物质变化符合一元线性回归模型...     

饲用杂交高粱和苏丹草饲喂草鱼研究

在高温高湿条件下，饲用杂交高粱和苏丹草长势良好，饲用杂交 高粱在株高1.0-1.5m高时鲜草产量可达37500kg/hm^2，茎叶比为1：0.92，可利用产量为17767.5kg/hm^2。苏丹草鲜草产量为18500kg/hm^2，茎叶比为1：0.40，可利用鲜草产量7400kg/hm^2。草鱼对饲用杂交高粱和苏丹草的采食率分别为36.56%和34.52%，摄食量分别为6.14g/天条和6.45g/天条，试验证明HCN对草鱼无毒副作用，其含量随着生长高度的增加而下降。     

Optimum Stand Height for Forage Brown Midrib Sorghum × Sudangrass in North-eastern USA

Brown midrib sorghum × sudangrass is attracting attention in the north‐eastern USA because of its ability to produce acceptable forage yields on marginal corn ground. Other potential advantages include conservation of soil on highly erosive ground, the possibility to spread manure mid‐summer (after first cutting) when runoff risk is minimal, greatly reduced needs for herbicides and the potential to reduce the importation of phosphorus onto the farm. Best management practices need to be developed to take full advantage of the crop in the north‐east. Seven field studies were conducted from 2000 to 2002 in four different agricultural regions in New York to determine the time of harvest optimum for yield and quality in one‐ to three‐cut management systems. Yield, rather than a change in forage quality indicators, was the key determining factor for estimated milk production. However, to prevent the shift from vegetative to reproductive growth (and associated decline in quality) and to better manage the amount of water at harvest, we recommend that in the north‐eastern USA brown midrib sorghum sudangrass be managed using a two‐cut system with harvest taking place when stand heights are about 125 cm or less.     

不同防褐化措施对苏丹草愈伤诱导以及抗褐化的效果研究

苏丹草组织材料在组织培养过程中会产生酚类物质,影响愈伤组织的生长,甚至导致愈伤组织死亡。本试验以苏丹草幼穗为外植体,探讨了不同防褐化措施对苏丹草愈伤诱导的影响及抗褐化的效果防止。结果表明,活性炭、V_C、PVP和AgNO₃均能不同程度地提高愈伤诱导率和降低褐化率。其中,培养基中低浓度的蔗糖(10~20 g/L)能降低褐化率,但同时也降低了愈伤诱导率,而高浓度的蔗糖(40~50 g/L)能提高愈伤诱导率但同时也增加了褐化率。柠檬酸能提高愈伤诱导率但不能防止褐化。当活性炭的添加量为0.15 g/L时,愈伤的诱导及褐化防止效果最好。     

新苏二号苏丹草新品种的选育(1987～1991年)

新苏二号苏丹草品种(Sorghum sudanense(Piper.)Stapf.CV.XinsuNo.2)是199J年11月经全国牧草品种审定委员会审定通过的国家注册新品种.本文简介了选育的方法、品比、多点及生产等系列试验的结果以及新品种的特征特性、相应的栽培技术要点和适宜的推广地区.新苏二号苏丹草原名890—1,种籽颖壳黑色,黑红色,植株高大、丰产性强,产草量高,早熟,成熟期相对集中。种子产量高,在肥水条件良好的情况下,丰产性表现更突出。     

散穗高粱与白壳苏丹草杂交F1及其染色体加倍植株ISSR分析

为了明确散穗高粱与白壳苏丹草杂交F1及其染色体加倍植株遗传差异性及其遗传距离,为下一步新品种育成利用奠定基础和提供科学依据。试验利用ISSR标记技术对散穗高粱与白壳苏丹草杂交F1及其染色体加倍植株进行多态性位点比较分析。结果表明：6条适宜引物共扩增得到重复性好的清晰条带164条,其中144条多态性条带,多态性比率达到86.9%;材料间的遗传距离变幅为0.2690~0.5923,散穗高粱与散穗高粱×白壳苏丹草F1加倍植株之间的遗传距离最远;供试材料以遗传距离0.26为基准可分为散穗高粱和白壳苏丹草;散穗高粱×白壳苏丹草杂种F1;散穗高粱×白壳苏丹草杂种F1加倍植株这三类。     

Magnesium accumulation and mineral balance in sudangrass as influenced by potassium,calcium and sodium

Abstract

Sudangrass (Sorghum sudanense, ‘Piper’ Stapf) was grown in the greenhouse in a slightly calcareous sample of Shano silt loam. The purpose of the study was to evaluate plant response to Mg and to determine any changes in Mg nutrition following individual or composite application of Mg, Ca, K and Na as nitrate compounds. The concentration of Mg in plant tissue decreased following K application and increased with each increment of Mg applied irrespective of variations in the proportions of Ca and Na included in the treatments. A base treatment including Ca, Na, and K applied with or without Mg showed a significant yield response to Mg. The Mg response was attributed to a more favorable ionic balance in the growth medium with respect to Mg because the soil was not particularly Mg deficient. Application of Mg in this case lowered the plant K concentration significantly, increased the concentration of Mg, and gave a lower K/(Ca+Mg) ratio in the foliage than was obtained without Mg. Results suggest that high levels of other nutrient cations may adversely affect the Mg nutrition of crops growing on alkaline soils not abundantly supplied with available Mg.     

Residual effects of sewage‐sludge application on plant and soil‐profile chemical composition

Abstract

Long‐term effects on plant and soil‐profile chemical composition imposed by a residential sewage sludge were studied on an Oxisol from Hawaii. Sludge was applied at 0, 45, 90, and 180 Mg/ha in 1983. An NPK‐fertilized treatment was included for comparison. Sudangrass (Sorghum bicolorL. Moench) was grown as a test crop in the 1983–84 and 1986–87 seasons. Soil samples for chemical analysis were taken in 1987 at three depths: 0–23 cm, 23–46 cm, and 46–69 cm.

Beneficial effects of sludge, measured 3 years after application (beginning of the 1986's planting), were evident by large yield increases on sludge‐amended soils relative to the unamended and the NPK‐fertilized soils. The first cutting produced approximately 5 Mg/ha of dry matter from the sludge treatments, regardless of rate, as compared with 3 and 1.5 Mg/ha from the NPK and the 0 treatments. Regrowths showed similar effect, though less dramatic; average yields were 2.6 Mg/ha with sludge and 1.6 Mg/ha without.

Heavy‐metal concentrations in plants were generally unaffected by sludge applications; probably because (i) heavy‐metal contents of the sludge were low, and (ii) soil pH was increased by sludge.

Remarkable increases in pH, exchangeable Ca and extractable P, and resultant decreases in exchangeable Al, in all three soil layers of sludge‐amended soils suggest that surface application of a low heavy‐metal sludge could serve to correct subsoil acidity and enhance subsoil P availability.