基于HSV与形状特征融合的花椒图像识别

光照条件变化会对花椒目标识别率产生影响,关系到机器视觉技术能否有效应用于生产现场的花椒采摘。通过对HSV特性图像识别技术的分析,提出HSV和形状特征融合的花椒识别算法。该算法采用同态滤波方法对光照进行补偿,解决因为光照不均匀而导致的花椒识别率低的问题,最后利用花椒圆度特征,排除树枝及树叶等的干扰,实现花椒的准确识别。利用同态滤波方法对光照进行补偿,对于光照不强或者发生遮挡的花椒图像有较大改善,通过试验得出其平均识别率达到94.0%,比单独采用HSV特性识别时,在顺光,背光和遮阴条件下,识别率分别提高4%,13%和21%,此外在遮阴条件下运行时间缩短14.6%。为遮阴条件下提高花椒识别率提供一种方法。     

考虑雷诺数和形状影响的坝岸根石水平水流拖曳力系数修正

对于水利工程坝岸散抛根石冲揭失稳,水流作用下根石的拖曳力是重要的力学分析参数。该文基于黄河坝岸散抛根石的形状参数特征,利用水槽试验量测球体及不同形状块体受水流作用的水平拖曳力,研究雷诺数、物体形状指标与拖曳力相关关系及变化规律,明确影响因素,率定双因素影响下块体的拖曳力系数函数。结果表明,水下球体或近似球状物体的拖曳力系数,基本不受水流及物体形态影响,拖曳力系数趋于0.40～0.56;有棱角块体的水流拖曳力系数,块体雷诺数小于3×104的影响区域,系数函数呈双曲线趋势变化;块体雷诺数大于3×104的影响区域,迎水面宽高比不大于侧立面长高比,拖曳力系数趋于0.80～0.90,迎水面宽高比大于侧立面长高比,拖曳力系数趋于1.00～1.10。进一步通过试验修正了水流作用下不同形态物体的水平拖曳力系数,提出了块体雷诺数、形状参数双因素影响下物体水平拖曳力系数函数,得到了以不同物体来流方向投影响面积为基准的水平拖曳计算公式,经拟合公式的合理性分析与验证,拖曳力系数拟合优度达到0.90以上,平均相对误差为8.7%;修正后拖曳力平均相对误差仅为7.5%,公式计算效果良好,更准确地反映散抛根石的水下受力特征,为分析水下抛石受水流冲击离散形态提供理论依据。     

同期排卵处理母牛体温和活动量变化规律及效果分析

为探究同期排卵处理母牛体温和活动量变化规律及不同同期排卵技术处理效果，指导同期排卵技术优化。本研究自动监测了18头20月龄左右同期排卵（GnRH-PG-GnRH）处理荷斯坦母牛和17头产后40~60 d预同期排卵（PG-PG-GnRH-PG-GnRH）处理荷斯坦母牛的体温和活动量，应用自动检测系统进行母牛发情监测。结果发现，同期排卵处理母牛发情时阴道温度平均升高（0.43±0.20）℃，持续（12.37±2.73）h；活动量平均升高（18.28±18.61）倍，持续（11.00±1.68）h；排卵时阴道温度平均下降（0.20±0.10）℃，持续（11.00±1.68）h。自动化发情监测显示，同期排卵处理母牛7头发情并排卵；预同期排卵母牛GnRH处理前全部发情排卵。两种同期排卵处理，虽可改变母牛性周期进程，促进母牛性周期同步化，但均难以使母牛性周期完全同步。因此，将同期排卵-定时输精和发情鉴定技术科学结合才能取得更好的繁殖效果。     

生长素调控因子OsGRF4协同调控水稻粒形和稻瘟病抗性

【目的】水稻粒形为多基因控制的复杂数量性状,同时影响稻谷产量和稻米外观及碾磨品质,挖掘粒形相关基因并解析其遗传机制,对于水稻高产和优质品种选育具有重要意义。【方法】以前期利用大粒籼稻品种特大籼(TDX)为供体亲本、小粒粳稻品种日本晴(Nipponbare,NPB)为轮回亲本获得的一个大粒近等基因系,在水稻第2染色体上初定位粒形调控基因GS2.2(grain size 2.2)的基础上,对GS2.2基因进行了精细定位和候选功能基因的克隆鉴定。【结果】利用BC₄F₂群体中2887份极小粒单株及该群体中70份基因型杂合的大粒单株自交获得的BC₄F₃群体,将GS2.2基因精细定位在2M-7-1与2M-9之间的160.6 kb的区间内。该区间编码18个基因开放阅读框(ORF1-18)。测序发现ORF18基因在大粒近等基因系与小粒日本晴等位基因间存在5个SNP差异,ORF18编码生长素调控因子蛋白OsGRF4。采用CRISPR/Cas9基因编辑技术对大粒近等基因系中ORF18进行敲除,发现ORF18敲除株系粒长变短,证实ORF18是GS2.2的功能基因。进一步对ORF18大粒近等基因系和基因编辑敲除株系进行稻瘟菌室内离体和病圃接种鉴定,发现ORF18大粒近等基因系稻瘟病抗性增强,而基因编辑敲除株系稻瘟病抗性减弱,表明ORF18正调控水稻稻瘟病抗性。【结论】本研究发现的生长素调控因子OsGRF4协同调控水稻粒形和稻瘟病抗性,为协调水稻高产和抗性育种提供了重要的基因资源。     

Electron microscopic observations of sooty moulds on crape myrtle leaves

Sooty moulds on crape myrtle leaves were investigated using light and electron microscopy. The adaxial leaf surface was distinctly covered with soot‐like masses of dark brown hyphae and conidia. The main characteristics of the sooty moulds included stauroconidia, conidial clusters, hyphal degeneration and extracellular melanin depositions. Some conidia were round, measured ~10 μm in diameter, and mostly one‐septate; others were branched and multiseptate (stauroconidia). Based on their morphology, the sooty moulds were determined to consist of several component fungal species belonging to genera such as Antennaria, Metacapnodium and Tripospermum. Enclosed in electron‐dense melanin layers, hyphae and conidial clusters had concentric bodies exhibiting electron‐transparent cores and electron‐dense shells with fibrillar sheaths. Concentric bodies are hypothesized to function as multilayer lipid‐encapsulated nanobubbles or eukaryotic gas vesicles for cytoplasmic volume control. Intrahyphal hyphae possessed electron‐dense cytoplasm and lipid globules. These results suggest that sooty moulds are equipped with melanized cell walls, multicelled resting structures, hyphal regeneration, intrahyphal growth and gas vesicles to adapt to their xeric phylloplane environment. Condensed and elongated starch granules in the chloroplasts of mesophyll tissues may indicate the acclimation of the sooty leaf regions to light reduction and temperature increase.     

鸭种蛋质量和蛋形指数对孵化效果的影响

【目的】研究鸭入孵蛋质量与蛋形指数对孵化过程中种蛋质量、孵化成绩及雏鸭初生体质量的影响。【方法】将同一天收集的黑鹜鸭(H)、建昌鸭(J)和农华肉鸭P系(P)种蛋测量其入孵蛋质量、长径和短径,计算蛋形指数。将种蛋分别按入孵蛋质量和蛋形指数分为3组,进行同批变温孵化,从孵化第7天起每3d照蛋1次,称量并记录种蛋质量,剔除无精蛋和死胚蛋,从孵化第26天起每天检查出雏情况,记录雏鸭初生体质量。计算入孵蛋孵化率、受精蛋孵化率、孵化期间种蛋质量损失量和质量损失率,分析鸭入孵蛋质量和蛋形指数对孵化效果的影响。【结果】3个品种不同入孵蛋质量和蛋形指数的种蛋质量损失量和质量损失率无显著差异,且变化趋势相同。入孵蛋质量分组方面,黑鹜鸭1组(质量64.84g/枚)、建昌鸭1组(质量76.94g/枚)和农华肉鸭P系1组(质量88.03g/枚)的受精蛋孵化率最高,黑鹜鸭2组(质量64.84~76.28g/枚)、建昌鸭1组(质量76.94g/枚)和农华肉鸭P系1组(质量88.03g/枚)的入孵蛋孵化率最高;蛋形指数分组方面,黑鹜鸭3组(1.42)、建昌鸭1组(1.30)和农华肉鸭P系3组(1.39)的受精蛋孵化率和入孵蛋孵化率均最高。各品种雏鸭初生体质量与入孵蛋质量呈显著正相关(P0.05),与蛋形指数无明显相关性(P0.05)。【结论】孵化过程中鸭种蛋的质量损失量和质量损失率与入孵蛋质量和蛋形指数无关,不同鸭品种的最佳入孵蛋质量与蛋形指数范围不同;雏鸭初生体质量随入孵蛋质量的增大而增大,但蛋形指数对其无显著影响。     

8种野生葱属植物的叶形态特征及其分类学意义研究

【目的】比较8种野生葱属植物的叶形态特征,为其分类学研究和生态适应性机制分析提供依据。【方法】以分布于新疆不同生境的8种野生葱属植物齿丝山韭、实葶葱、新疆蒜、健蒜、多籽蒜、奇台蒜、喀纳斯蒜和乌鲁木齐蒜为研究对象,采用田间观测和树胶制片法,测定其叶片数量、长度、宽度等指标,观察其解剖结构异同;通过相关性分析和聚类分析,研究叶片表皮性状之间的关系以及性状的分类学意义。【结果】8种葱属植物的叶形态和微形态存在差异,实葶葱和齿丝山韭叶直立,其余呈不同程度倒伏;实葶葱叶圆柱形,其余叶均为条形;实葶葱叶表面被蜡粉,其余均为光滑;实葶葱叶表皮细胞矩形,其余均为菱形;实葶葱垂周壁直线型,其余均为弧线形。8种植物叶片均为双面气孔型,气孔椭圆形,保卫细胞肾形,无副卫细胞,保卫细胞不同程度下陷。基于叶表皮结构性状的聚类分析结果显示,供试8种材料分为3类,齿丝山韭和实葶葱分别聚为一类,其余6种聚为一类。【结论】叶形态、表皮细胞形状、垂周壁形状、表皮细胞密度和气孔指数大小可为种的界定提供重要的形态分类学依据,具有分类学意义。叶片上表皮细胞比下表皮细胞可以提供更为全面的微形态特征。新疆8种野生葱属植物的叶片形态和微形态结构均呈现一定的抗旱和抗寒特征。     

Effects of dietary protein to energy ratios on growth,body composition and digestive enzyme activities in Chinese mitten‐handed crab,Eriocheir sinensis

This study aimed to determine the optimal protein to energy ratio (P/E ratio) and evaluate the effect of dietary protein and lipid levels on growth performance, body composition and digestive enzymes activities in Chinese mitten‐handed crab, Eriocheir sinensis. Nine practical diets containing three levels both for protein (DP 30%, 35% and 40%) and lipid (DL 2%, 7% and 12%) with P/E ratios ranging from 13.69 to 19.79 mg KJ^?1 were fed to four replicates of crabs (3.39 ± 0.10 g) for 10 weeks. Weight gain increased significantly with the increase in DP level at each DL level. Moreover, weight gain increased in crabs fed with diets containing DL level from 2% to 12% and DP level from 30% to 35%. However, the diet containing 40% DP and 12% DL levels significantly decreased the growth performance and protein efficiency of the crabs. The whole crab and hepatopancreas lipid contents also increased as dietary lipid increased, but not dietary protein. The total protease activity increased significantly with the increase in dietary protein at each lipid level. The lipase activity was statistically comparable among different DL levels at each DP level. Taken together, the crab fed the diet containing 35% protein and 12% lipid levels with P/E 15.77 mg KJ^?1 revealed optimal growth, feed utilization efficiency and digestive enzymes activities. Moreover, our study indicated that the higher dietary lipid level at a relatively lower dietary protein level could provide protein sparing effect in Eriocheir sinensis.     

Effect of dietary phosphorus levels on growth and body composition of crucian carp,Carassius auratus under indoor and outdoor experiments

Indoor and outdoor experiments were carried out simultaneously to evaluate the effects of dietary phosphorus levels on growth performance and body composition of crucian carp. Monocalcium was used to formulate extruded feed containing available phosphorus (AP) of 1.5 (D1), 4.7 (D2), 6.3 (D3) and 9.0 (D4) g kg^?1. Twelve 500‐L recirculating tanks were assigned to four triplicate groups with each tank stocked with 15 juveniles (39.88 ± 0.14 g) for indoor experiment. Twelve polyethylene enclosures were assigned to four groups with each one stocked with 120 juveniles (44.08 ± 1.36 g). After 8 weeks of feeding, survival ranged from 96% to 100%. Weight gain, special growth rate, protein efficiency ratio and feed conversion rate did not show significant differences among dietary treatments in both experiments. Fish cultured in the enclosures grew better, although D1 and D2 treatments did not reach significant level. Crude protein and phosphorus content of the fish were not significantly affected by dietary phosphorus level. Moisture, crude lipid, crude ash and vertebrae phosphorus were significantly affected by different phosphorus levels. Based on vertebrae phosphorus, crucian carp cultured in the tanks and in the enclosures showed phosphorus deficiency under 4.7 g kg^?1 and 6.3 g kg^?1 AP, respectively.     

Effects of dietary protein and lipid levels with different protein‐to‐energy ratios on growth performance,feed utilization and body composition of juvenile red‐spotted grouper,Epinephelus akaara

An 8‐week feeding trial was conducted to assess dietary protein and lipid levels on growth performance, feed utilization and body composition of juvenile red‐spotted grouper (7.85 ± 0.03 g fish^?1). Nine semi‐purified diets were formulated containing varying protein levels (440–520 g kg^?1, dry matter) and lipid levels (60–120 g kg^?1, dry matter). The weight gain of juvenile Epinephelus akaara was affected by dietary protein (p = .005) and its interaction with dietary lipid (p = .020). Viscerosomatic index, intraperitoneal fat ratio and whole‐body lipid level increased with increasing dietary lipid level (p < .001). Nitrogen retention was not affected by dietary protein and lipid, while lipid retention decreased with increasing dietary lipid level (p < .001). The plasma blood urea nitrogen increased with increasing dietary protein level (p = .003). This study showed that diet with 520 g kg^?1 protein and 60 g kg^?1 lipid with 30.58 mg kJ^?1 P:E provided a maximal growth for this species. Moreover, an increase in dietary lipid levels (from 60 to 90 g kg^?1) could reduce the protein requirement (from 520 to 480 g kg^?1) without affecting the growth performance, while higher fat deposition was observed in fish fed high‐lipid diets.