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21.
A viral isolate from Egypt associated with symptoms of enations and leaf curling on hollyhock (Althea rosea) was characterized at the cytopathological and molecular levels. Microscopic observations showed that enations resulted from a reorganization of the vascular tissues, including activation of a cambial activity in the phloem, the development of a palisade parenchyma in place of a spongy one and the differentiation of minor vascular tissues. From this isolate, the full-length DNA-A of a begomovirus (family Geminiviridae) was cloned and sequenced. This genome exhibited a genetic organization similar to that of other old-world begomoviruses like Tomato yellow leaf curl virus from Israel and Ageratum yellow vein virus from Singapore. However, its sequence was significantly distinct (similarity < 69%) from any other geminivirus. This begomovirus was thus considered as representative of a new viral species named Althea rosea enation virus (AREV). AREV was agroinfectious on Nicotiana benthamiana, on which it induced a severe leaf-curling and vein distortion, but could not re-establish infection on A. rosea. To determine if AREV was also associated with a similar disease affecting okra in Upper-Egypt, the partial sequence of the coat protein gene of an isolate was determined. It exhibited 90% nt identity with the hollyhock isolate (97% amino acid), suggesting a genetic heterogeneity in the begomovirus population associated with the enation diseases.  相似文献   
22.
Broiler carcass skin color is important in China, the United States, Mexico, and other countries. The present study evaluated the use of natural and synthetic pigments in broiler diets at different commercial levels. The experiment included 288 fifty-day-old Da-Ma-Hua birds, divided into 6 treatments. Birds in 4 treatments were fed a basal diet consisting of 2, 3, 4, or 5% okra [Abelmoschus esculentus (L.) Moench Meth., also known as abelmosk or ram-horn bean] meal, respectively. Birds in another treatment received a basal diet without okra, and birds in a sixth treatment were fed a blend of 25 g/metric ton of 10% canthaxanthin and 50 g/metric ton of 10% carotenoic acid, β-apo-8′-ethylesters. Each treatment consisted of 3 replicates of 16 birds each. The experiment lasted 6 wk. Skin color was measured with a Kemin color fan after slaughter and chilling at wk 2, 3, 4, 5, and 6 of treatment. Pigmentation of the chicken skin and abdominal fat were significantly improved (P < 0.05) in the 4 and 5% okra treatments. The pigmentation effect reached a satisfactory level after 4 wk of treatment. The rank of pigmentation in different parts of the body of a bird was shank > breast > abdomen > back. The addition of okra meal had no significant influence on daily gain or the feed-to-gain ratio (P > 0.05). This study shows that xanthophyll-rich okra meal can be used as a natural pigment source in poultry feed, which may allow pigment use and feed costs to be reduced.  相似文献   
23.
以9个黄秋葵品种为基本材料,通过连续多代自交获得自交系后,分析和比较了各个自交系的性状特点,选择了8个性状较为优良的自交系作为亲本进行配对,制成了14个单交种材料,同时,首次尝试将黄秋葵与红秋葵进行杂交,获得了果实颜色介于两亲本之间的中间类型。通过调查和比较,筛选出2个具有产量优势的杂交组合。在杂交育种过程中,也发现了可利用叶柄颜色作为标记性状来生产杂交黄秋葵种苗的新方法。  相似文献   
24.
建阳市黄秋葵害虫的发生与防治   总被引:1,自引:1,他引:0  
总结了建阳市黄秋葵主要害虫棉大卷叶螟、斜纹夜蛾、茶黄螨和蚜虫的形态特征、发生特点及其防治方法,以期为黄秋葵害虫的防治提供参考。  相似文献   
25.
通过对加勒比地区引进的黄秋葵新品种美洲1号进行引种和栽培试验,对其生育期、农艺性状、产量性状及抗性等方面进行调查研究。结果表明,美洲1号黄秋葵是一种熟期晚、果大、抗性强、产量高、适应性好的品种,在汕尾市等南亚热带地区有一定的推广应用价值。  相似文献   
26.
不同种植时间对黄秋葵后期生长影响的研究结果表明院邢台市黄秋葵适合种植的时间大概在4月上中旬;种植时间越早,黄秋葵的根茎部位越粗壮,且差异明显;提前育苗,果实可以提前采摘且产量高,经济效益越大。  相似文献   
27.
为研究在饲料中添加不同量的黄秋葵对肉兔生产性能、脏器指数和血清生化指标的影响,试验选用35日龄健康新西兰肉兔120只,随机分成5组,每组3个重复,每个重复8只,预试期7 d,正试期28 d,试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组分别在基础日粮中添加1%、2%、3%和4%黄秋葵粉。结果表明:与对照组相比,试验Ⅰ、Ⅱ、Ⅲ组滴水损失率分别降低16.83%、15.63%和20.19%,差异显著(P < 0.05)|试验Ⅱ、Ⅲ组肉兔的期末重分别增加6.91%、8.81%,平均日增重分别增加16.91%、20.61%,肉品质的红度分别升高50%、56.74%,血清总蛋白分别升高12.44%、23.69%,白蛋白分别升高9.39%、22.91%,均差异显著(P < 0.05)|与对照组相比,试验Ⅱ、Ⅲ组料重比分别下降12.57%、15.64%,肉品的黄度分别降低20.22%、27.22%,血清甘油三脂分别降低9.87%、17.11%,均差异显著(P < 0.05)|与对照组相比,试验Ⅲ组兔肉的剪切力降低16.06%,熟肉率提高12.14%,血清尿素氮下降9.50%,均差异显著(P < 0.05)|各组肉兔的平均采食量、兔肉的亮度、血清葡萄糖、总胆固醇、谷丙转氨酶、谷草转氨酶及碱性磷酸酶活性均无显著差异(P > 0.05)。因此,肉兔饲料中黄秋葵的适宜添加量为3%。 [关键词] 黄秋葵|肉兔|生产性能|肉品质|血清生化指标  相似文献   
28.
29.
Summary Factor, Principal component and canonical analyses were used to study the extent of genetic diversity among 30 accessions of West African okra. Genetic variability among the accessions proved to be large. Pigmentation of various parts of the accessions and fruit characteristics contributed significantly to the total variation observed. Factor analysis and principal component analysis produced similar results which were substantially different from those produced by canonical analysis. The first three canonical variables accounted for 100% of the total variance while the number of pods per plant, and pod weight primarily accounted for the first canonical variable. Whereas the second canonical variable was primarily loaded by number of seeds per pod and fruit colour, the third canonical variable was comprised of a weight of 100 seeds and number of epicalyx segments.The level of variability observed supports the opinion (Stevels, 1988, 1990) that this okra type constitutes a separate species.  相似文献   
30.
The effects of a low-external-input soil fertility enhancement solution – hereafter termed ‘nitrolimigation’ were examined, as a preferred technique of applying nitrogen and calcium in the “Acid Sands” soils of southern Nigeria. Two types of nitrogenous fertilizer sources [urea and liquid pig manure (LPM)] and two types of lime {limestone (CaCO3) and hydrated lime [Ca(OH)2]} were used both in greenhouse and in field experiments at varying levels: Urea [CO (NH2)2] 0, 40, 50, 80, 100, 120, and 150 kg ha?1; lime 0, 0.1, 0.3, 0.5, 1.0, 5.0, and 10.0 metric tonnes per hectare (t ha?1) and LPM 0, 30, 60, 90, and 120 t ha?1. The rates were arranged factorially and laid out in randomized complete block design (RCBD). The results indicated that combining lime at 9 t ha?1 and LPM at 90 t ha?1 in irrigation water had significant (P < 0.01) positive effects on the fertility status of the “Acid Sands” soils and growth of okra- Abelmoschus esculentus, the test crop. When urea was combined with hydrated lime, it reduced acidity and provided nutrient balance in the Acid Sands of Calabar. Total nitrogen was significantly (P < 0.01) boosted from 0.05 to 0.11%, base saturation (BS) from 46 to 62%, and exchange acidity was reduced from 2.93 to 1.35 cmol kg?1. Combining urea (46-0-0) at 80 kg ha?1 with lime (CaCO3) at 5 t ha?1 raised the soil pH from 4.4 to 7.1. Exchange acidity was reduced from 0.8 cmol kg?1 to a negligible value, but electrical conductivity was improved from 170.7 to 291.9 μS cm?1. When LPM and lime were combined, organic carbon was increased from 2.75 to 2.93%, BS was increased from 46.72 to 75.19%, and pH was raised from 6.0 to 6.73. Plant height was increased from 9.5 to 16.9 cm while mean number of leaves was also increased from 5.6 to 6.3 only with lower level of lime (3 t ha?1) and LPM at 90 t ha?1. Of the nitrogen and calcium sources, LPM and limestone were better at 120 t ha?1 and 9 t ha?1, respectively, to offset soil acidity, boost nutrient availability, and provide balanced nutrition to arable crops grown on the “Acid Sands” of southern Nigeria.  相似文献   
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