桃花粉育性与花药颜色的关系及其SSR分子标记

以李属桃亚属的637份桃品种种质和栽培种瑞光19×Summergrand杂交的138株F1群体为试材,对桃花粉育性与花药颜色的关系及其SSR分子标记进行研究。结果表明:在所有品种中,橘红花药最多,占总份数的91.2%,其中绝大部分花粉可育;橘黄和黄色花药的种质数量次之;白色和浅褐花药的种质最少,且均表现为花粉不稔;整体表现为红色和黄色花药与花粉可育具有较强的正相关性。本试验从122对SSR引物中筛选出2对与花粉育性性状连锁的标记CPDCT013和CP-SCT012,根据这2个标记参考整合参考图谱的位置,将控制花粉育性的基因定位在桃第6条染色体上端。对已经报道的2个桃花粉育性标记CPPCT004和NNJ-I以及第6条连锁群的其他SSR位点在花粉育性不同的24个品种上验证,结果表明只有UDP96-001(125bp)可以用于桃花粉育性的分子标记辅助育种。     

Mating behavior of the cabbage beetle, Colaphellus bowringi (Coleoptera: Chrysomelidae)

Abstract  Circadian mating rhythms, mating frequency, mating duration, and the effect of mating duration on fecundity and fertility in the cabbage beetle, Colaphellus bowringi were investigated in the laboratory. Mating occurred throughout the 24-h cycle but the majority of copulations occurred in the photophase with two apparent peaks, one at 8:00 and another at 16:00. Mating frequency observations for 10 consecutive days indicated that pre-mating period of C. bowringi was about 4 days, and pairs mated an average of 5 times per day and an average of 40 times during the first 10 days. There was a negative correlation between mating frequency and mating duration during the consecutive mating. The mean duration of the first copulation (136.24 ± 4.62 min) was significantly longer than those of the second (57.87 ± 2.03 min), third (53.05 ± 2.05 min) and fourth copulation (30.86 ± 2.98 min). Fecundity showed a slight increase with increasing mating duration but no significant difference among treatments. However, fertility was significantly influenced by the mating duration in this species. Mating of 20-min duration did not produce viable eggs. The mean percentage of fertile eggs with completed mating duration (204.43 ± 18.96 min, 56.75% fertile eggs) was significantly higher than those with 60 min (39.55%) and 30 min (17.91%) mating duration, suggesting that the longer mating duration might be associated with transfer of more sperm that are used to increase the fertility of eggs.     

An Evaluation of Diazacon as a Potential Contraceptive in Non-Native Rose-Ringed Parakeets

ABSTRACT Rose-ringed parakeets (Psittacula krameri) have become widely established outside their native range through accidental or deliberate release. Potential economic impacts on agriculture, conservation concerns, and mixed public opinion regarding the species have highlighted the need to develop effective but humane management options. Fertility control might provide such a solution if a safe and environmentally benign contraceptive was available. The chemical 20,25-diazacholesterol dihydrochloride (diazacon) has previously been used to reduce reproductive output in avian species through reduction of blood cholesterol and cholesterol-dependent reproductive hormones. We orally dosed captive rose-ringed parakeets with a solution of either 9 mg/kg or 18 mg/kg of diazacon for up to 10 days and found that a dose of 18 mg/kg for 10 days temporarily reduced blood cholesterol levels with no adverse side effects. We evaluated this dose level in a captive population in semi-natural conditions during the 2008 breeding season and found a significant decrease in fertility. We concluded that diazacon has potential for fertility control in this species if a suitable formulation and delivery system is developed for free-living populations.     

Living on the Edge: Viability of Moose in Northeastern Minnesota

ABSTRACT North temperate species on the southern edge of their distribution are especially at risk to climate-induced changes. One such species is the moose (Alces alces), whose continental United States distribution is restricted to northern states or northern portions of the Rocky Mountain cordillera. We used a series of matrix models to evaluate the demographic implications of estimated survival and reproduction schedules for a moose population in northeastern Minnesota, USA, between 2002 and 2008. We used data from a telemetry study to calculate adult survival rates and estimated calf survival and fertility of adult females by using results of helicopter surveys. Estimated age- and year-specific survival rates showed a sinusoidal temporal pattern during our study and were lower for younger and old-aged animals. Estimates of annual adult survival (when assumed to be constant for ages >1.7 yr old) ranged from 0.74 to 0.85. Annual calf survival averaged 0.40, and the annual ratio of calves born to radiocollared females averaged 0.78. Point estimates for the finite rate of increase (λ) from yearly matrices ranged from 0.67 to 0.98 during our 6-year study, indicative of a long-term declining population. Assuming each matrix to be equally likely to occur in the future, we estimated a long-term stochastic growth rate of 0.85. Even if heat stress is not responsible for current levels of survival, continuation of this growth rate will ultimately result in a northward shift of the southern edge of moose distribution. Population growth rate, and its uncertainty, was most sensitive to changes in estimated adult survival rates. The relative importance of adult survival to population viability has important implications for harvest of large herbivores and the collection of information on wildlife fertility.     

Assessment of hydroxypropyl methylcellulose, propylene glycol, polysorbate 80, and hydroxypropyl-β-cyclodextrin for use in developmental and reproductive toxicology studies

BACKGROUND: A series of studies were conducted to assess Polysorbate 80 (PS80), Propylene Glycol (PG), and Hydroxypropyl‐β‐Cyclodextrin (HPβCD), when compared with Hydroxypropyl Methylcellulose (MC) in developmental and reproductive toxicology (DART) studies. METHODS: In the rat fertility study, 20 mg/kg MC, 10 mg/kg PS80, 1,000 mg/kg PG, 500 mg/kg HPβCD or 1,000 mg/kg HPβCD were administered orally before/during mating, and on gestation Day (GD) 0–7, followed by an assessment of embryonic development on GD 14. In the rat and rabbit teratology studies, the doses of MC, PS80, PG, and HPβCD were the same as those in the fertility study. In these teratology studies, pregnant females were dosed during the period of organogenesis, followed by an assessment of fetal external, visceral, and skeletal development. RESULTS: In the rat fertility and rat teratology studies, PS80, PG, and HPβCD did not exhibit toxicity, when compared with MC. Similarly, in the rabbit teratology study, there was no PS80 or PG‐related toxicity, when compared with MC. However, individual rabbits in the 500 and 1,000 mg/kg HPβCD groups exhibited maternal toxicity, which included stool findings, decreased food consumption, and body weight gain. Furthermore, one rabbit each in the 500 and 1,000 mg/kg HPβCD groups exhibited evidence of abortion, which was considered secondary to maternal toxicity. CONCLUSIONS: Although HPβCD was not well tolerated in rabbits at doses of 500 and 1,000 mg/kg, PS80 and PG were comparable to MC and should be considered for use in developmental and reproductive toxicology studies. Birth Defects Res (Part B) 89:504–516,2010. © 2010 Wiley‐Liss, Inc.     

Use of intrauterine devices as a means of contraception in a colony of chimpanzees (Pan troglodytes)

The uncontrolled reproduction of the captive chimpanzee colony at the Primate Centre, CIRMF, Gabon, has led to high neonatal mortality. The only solution meeting ethical, financial, and practical considerations was to attempt reversible physical contraception using intrauterine devices (IUDs). Human IUDs were inserted into 21 females of various ages, parities, and stages of the menstrual cycle. Over a 30-month period, five of the study animals became pregnant. This reduction of conception rate, with minimal side effects, demonstrates the reliability of IUDs for controlling reproduction of chimpanzee colonies.     

Effect of farnesol on Candida dubliniensis morphogenesis

AIMS: Cell-cell signalling in Candida albicans is a known phenomenon and farnesol was identified as a quorum sensing molecule determining the yeast morphology. The aim of this work was to verify if farnesol had a similar effect on Candida dubliniensis, highlighting the effect of farnesol on Candida spp. morphogenesis. METHODS AND RESULTS: Two different strains of C. dubliniensis and one of C. albicans were grown both in RPMI 1640 and in serum in the presence of absence of farnesol. At 150 micromol l(-1) farnesol the growth rate of both Candida species was not affected. On the contrary, farnesol inhibited hyphae and pseudohyphae formation in C. dubliniensis. CONCLUSION: Farnesol seems to mediate cell morphology in both Candida species. SIGNIFICANCE AND IMPACT OF THE STUDY: The effect of farnesol on C. dubliniensis morphology was not reported previously.     

粘类小麦细胞质雄性不育系育性基因的地区分布

以具4种细胞质、2种核类型的粘类小麦雄性不育系为测验种,对309份来自国内外不同地区普通小麦品种对应粘类小麦不育系的育性恢复和保持关系进行调查,研究粘类小麦雄性不育系育性基因的地理分布.结果表明:(1)普通小麦品种中广泛存在着粘类雄性不育系的恢复基因,所配组合中,高恢复度以上的组合占到45.24%;(2)所配组合F1小穗结实率范围在0~91.35%之间,其中0和60%~80%的分布范围较多;(3)具有恢复能力的品种在供试6个地区均有分布,但比例不同,中国南方、新疆内陆、青藏高原等春麦地区高,可育品种的分布比例均超过50%;具有育性保持作用的品种在中国黄淮海暖温带冬麦气候生态区和加拿大地区分布较多,在新疆麦区分布最少;(4)恢复度80%以上的品种在6个地区均有分布,但在各地区供试材料中的比例都不高.