生物活性水对番茄种子萌发及幼苗生长的影响

用生物活性水对番茄种子进行浸种处理,稀释倍数分别为10、100、200、400、800,以清水作为对照,探索生物活性水对番茄种子萌发及幼苗生长的影响。结果表明:番茄种子发芽势、发芽率、幼苗株高、根长及叶绿素含量(SPAD)均高于对照,其中稀释100倍的生物活性水最有利于番茄种子萌发,稀释100倍和200倍的生物活性水均有利于促进主根伸长,且生物活性水在一定范围内存在浓度效应。     

A parametric and microstructural study of the formation of gluten network in mixed flour–water batter

The mechanism of gluten network development is still unclear and remains difficult to study since gluten network formation in bread dough is a rather quick process. In order to better characterize this dynamic event, we slowed down its kinetics by increasing the dough water content. During mixing, performed with a planetary mixer at variable mixing speeds and flour/water ratios, the torque was recorded. Common flours from wheat cultivars Orvantis, Caphorn and Isengrain, similar in composition and Farinograph parameters, were studied.     

Short-term transportation in a small vehicle affects the physiological state and subsequent water consumption in goats

We investigated the physiological effects on goats of transportation for one hour in a small truck. We also investigated food and water consumption after transportation. Eight adult goats (four castrated males and four ovariectomized females) were used. Plasma levels of cortisol, glucose and free fatty acids increased significantly within 15 min of the start of transportation, and these higher levels were maintained throughout transportation. These results indicate that transportation in a small truck activates the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system in goats. Despite activation of the sympathetic nervous system, heart rate (HR) in subjected animals during transportation did not differ from during the control animals, which were housed in their usual pen. However, after the transportation had ended and the goats started to eat fodder, HR increased significantly. There was no difference in the amount of food consumption between the control and transported goats. Water consumption in the first three hours after transportation was significantly lower in the transported goats than in the controls for the equivalent period. In the subsequent three hours, however, the transported goats consumed more water than the controls. Consequently, the total water consumption of the transported goats did not differ from that of the controls during the six hours after transportation. In conclusion, short-term transportation with a small vehicle activated the HPA axis and the sympathetic nervous system in goats. HR was not increased during transportation, but after the transportation had ended HR in transported goats was higher than that in control goats. After transportation, goats had consumed the same amount of food as control goats, but water consumption during three hours after the transportation was lower than that of control goats.     

Incomplete systemic movement of Xanthomonas campestris pv. musacearum and the occurrence of latent infections in xanthomonas wilt‐infected banana mats

Management of banana xanthomonas wilt (XW) (caused by Xanthomonas campestris pv. musacearum, Xcm) has been impeded by poor adoption of control options that are complex, cumbersome and costly. To improve XW management, this study investigated Xcm survival and latent infections in subsequent generations, survival of latently infected planting materials (suckers), incidence of latent infections in symptomless plants in mats having diseased plants, and XW status across farms and markets in districts previously devastated but currently endemic. On‐station experiments were protected from new infections. Latent bacteria at low levels were detected in up to 20% of the third generation suckers, with a significant (P < 0·05) reduction (43–20%) in subsequent generations. Only 3–6% of latently infected suckers succumbed to XW. Incidence of Xcm in symptomless suckers from farmers' fields (with up to 70% incidence) was low (3%) while it increased (8–25%) with disease severity in mats in controlled experiments. In the surveyed districts, incidence had significantly declined with yields observed to have recovered relative to earlier reports, although latent infections remained high. This study provides evidence that if new infections are prevented, fields with high XW incidence can be rejuvenated. It showed incomplete systemic movement of Xcm in mats coupled to a gradual decline of bacterial load in subsequent generations to levels that cannot initiate disease. These studies explain the current successes in farms practising single diseased plant removal instead of whole mat rouging, and gives hope to farmers lacking access to clean planting material.     

Preparation and Study of a Novel,Environmentally Friendly Seed-Coating Agent for Wheat

Traditional seed-coating agents are widespread and used in crop protection. However, the coatings can pose an environmental and health hazard. In this study, a novel wheat seed-coating agent was prepared by using natural polysaccharide as the main raw material, which produces bacteriostatic activity and enhances the germination and quality of seeds. The optimum formula of this seed-coating agent was ultimately determined through a series of laboratory experiments and field trials. The results showed that the yield of wheat seeds treated with this novel seed-coating agent was increased by 10% and its material cost was decreased by 15% compared with the conventional toxic seed-coating agent. The toxicity of the novel seed-coating agent was also less than that of the traditional one. Therefore, this wheat seed-coating agent had obvious economic and environmental benefits.     

不同产田土壤速效磷对夏玉米的肥效分析

采用田间试验法,研究了磷肥对不同产田夏玉米性状、产量及产量构成因素的影响,旨为夏玉米合理施用磷肥提供科学依据。结果表明：高、中、低产夏玉米田最佳经济施磷量分别为50 kg/hm2、52 kg/hm2和47 kg/hm2。     

Effects of AI protocol and time interval from onset of estrus to AI on conception rate in Japanese Black cows

Two different artificial insemination (AI) protocols were investigated to determine the effect of the time interval from the onset of estrus (as detected by a pedometer) to the AI on the conception rate in Japanese Black cows. Seventy‐three cows were divided into two groups that received AI either after the induction of synchronized ovulation (synchronized AI group; n = 26) or at the time of observed estrus (control AI group; n = 47). Each group was further divided into two subgroups, which were artificially inseminated either 0–12 h (early AI group; n = 21) or 12–24 h (late AI group; n = 52) after the onset of estrus. There was no significant difference in the conception rate between the synchronized AI and control AI groups. The AI protocol and the detection of estrus using a threshold of counted steps (as measured by a pedometer) in this study could be effective for planned reproduction management without the observation of standing estrus in Japanese Black cows.     

旱地矮化苹果园当季氮肥在土壤剖面的累积与淋溶效应

为研究旱地矮化苹果树当季肥料氮在土壤中的累积与淋溶效应,采用土钻采样法与¹⁵N同位素示踪技术,测定了6 a生晚熟矮化‘延长红’苹果园土壤剖面（0~300 cm）的氮素累积分布特征与当季氮肥残留。结果表明：土壤含水率与硝态氮含量变化表现出较强的一致性,不施肥CK、减氮施肥N400与常规施肥N800处理硝态氮在80~140 cm土层存在明显富集现象,其含量峰值分别为174.9、194.8 mg·kg^-1与211.1 mg·kg^-1。CK、N400与N800处理0~300 cm土壤剖面中,全氮累积量分别为10 927.3、13 734.8 kg·hm^-2与15 645.4 kg·hm^-2,硝态氮累积量分别为1 873.5、2 353.9 kg·hm^-2与2 892.7 kg·hm^-2,铵态氮累积量分别为12.2、42.6 kg·hm^-2与44.4 kg·hm^-2。N400和N800处理下果园土壤中各土层（0~300 cm）氮素来自当季氮肥的比例分别为0.10%~1.50%和0.18%~2.03%。当季氮肥在0~300 cm深度各土层均有残留且主要集中在0~140 cm土层;80~100 cm土层的全氮来自当季氮肥的比例（减氮施肥N400和常规施肥N800分别为1.50%与2.03%）显著高于其他土层。N400处理下TN-¹⁵N、NO^-₃-¹⁵N、NH⁺₄-¹⁵N的残留率分别为21.6%、19.2%、0.2%,N800处理分别为48.8%、39.3%、0.3%,土壤中氮的残留率随着施氮量的增加显著增加,且以硝态氮为主。100~300 cm土层中减氮施肥N400与常规施肥N800处理NO^-₃-¹⁵N残留率分别为8.5%与25.0%,当季氮肥淋溶出根区（0~80 cm）现象明显。最佳施肥量及施肥量对产量的影响在N400的基础上仍有待进一步研究确定。     

Effect of relationships among clinical mastitis incidence,reproductive performance,and culling rate on the lifetime of dairy cows at Hiroshima University Farm

Farm managers' decision to cull dairy cows is based on the cows' milk production, history of disorder(s), and reproductive performance, each of which affects dairy cows' lifetime (herd life and productive lifespan). We investigated the relationships among the incidence of clinical mastitis (CM), the reproductive performance, and the culling rate. We also assessed the effects of these relationships on the lifetimes of dairy cows, using the records made before and after the introduction of an automatic milking system (AMS) at Hiroshima University Farm. Milk yield, CM incidence density, and culling rate of dairy cows increased after the AMS introduction. The CM incidence was associated with an elongation of the calving interval in cows with the same parity. CM in the 1st parity might have caused the reductions of the cows' lifetime and their parity at culling. A higher age at first calving (AFC) was associated with an increase in culling rate but did not lead to a significant decrease in lifetime. Investigations of the factors mediating CM in the 1st parity or AFC with CM incidence or culling rate in the later stages might contribute to the control of lifetime of dairy cows.     

工厂化猪场不同猪群死亡率与季节的关系初探

通过对哺乳仔猪群、保育群、育成群各月死亡率的统计分析发现,冬季低温对哺乳仔猪群、保育群死亡率的影响远远大于夏季高温的影响。冬季低温对保育群的死亡率影响最大,而对育成群几乎没有影响。夏季高温对不同猪群的死亡率有不同程度的影响力。不同猪群对温度反应的快慢、强度及持续期各不相同。