早花能促进美洲南瓜早熟和高产，并能拮抗生物和非生物胁迫，是美洲南瓜重要的农艺性状。在本研究中，美洲南瓜自交系‘19’的第一雌花开花天数明显少于自交系‘113’，表现为稳定的早花性状。遗传分析表明，第一雌花开花天数是一个可遗传的数量性状，受多基因控制。采用QTL测序结合连锁分析的方法，在第4、11和20号染色体上鉴定出3个用于第一雌花开花天数的QTL。为了验证这一结果，利用不同环境条件下生长的F₂群体，开发InDel标记对第一雌花开花天数进行QTL定位分析。利用R/qtl软件的复合区间作图方法，在所有环境条件下均鉴定出1个主位点，位于20号染色体117 kb的候选区域。通过基因注释、基因序列比对和qRT-PCR分析，发现编码环指蛋白的Cp4.1LG20g08050基因可能是一个对美洲南瓜早花起相反调控作用的候选基因。总之，本研究结果为更好地认识美洲南瓜早花性状，为美洲南瓜的早花育种策略奠定了基础。

To dissect the genetic control of the sensory and textural quality traits of Chinese white noodles, a population of recombinant inbred lines (RILs), derived from the cross of waxy wheat Nuomai 1 (NM1) and Gaocheng 8901 (Gc8901), was used.  The RILs were tested in three different environments to determine the role of environmental effects on quantitative trait loci (QTL) analysis.  A total of 45 QTLs with additive effects for 17 noodle sensory and textural properties under three environments were mapped on 15 chromosomes.  These QTLs showed 4.23–42.68% of the phenotypic variance explained (PVE).  Nineteen major QTLs were distributed on chromosomes 1B, 1D, 2A, 3B, 3D, 4A, and 6A, explaining more than 10% of the phenotypic variance (PV).  Clusters were detected on chromosomes 2B (3 QTLs), 3B (11 QTLs) and 4A (5 QTLs).  The cluster detected on chromosome 4A was close to the Wx-B1 marker.  Five co-located QTLs with additive effects were identified on chromosomes 2B, 3D, 4A, 6A, and 7B.  The two major QTLs, Qadh.sdau-3B.1 and Qspr.sdau-3B.1, in cluster wPt666008–wPt5870 on chromosome 3B were detected in three different environments, which perhaps can be directly applied to improve the textural properties of noodles.  These findings could offer evidence for the selection or development of new wheat varieties with noodle quality using molecular marker-assisted selection (MAS).

    In this study, two ploidy mutant lines of Myrica rubra cv. Dongkui (DK) were identified and named as DB1 and DB2. The floral organ, leaf cell structure, ploidy, and number of chromosomes of the two mutants were investigated. Meanwhile, anthocyanin contents at different developmental stages were analyzed, and the Cy-3-glu contents of DB1 and DB2 at the full ripe stages are significantly higher than that of DK by 27.84 and 23.51%, respectively. Furthermore, 6 RNA libraries at two developmental stages (young fruit stage and full ripe stage) were built for RNA-Seq. By mapping to the reference database, 28 407, 28 043, and 28 683 genes were detected in the young fruit of DB1, DB2, and DK, respectively, while 28 040, 22 256, and 27 351 genes were detected in the full ripe stage, respectively. There were 281 differentially expressed genes between DB1 and DK, with 123 and 158 genes up-regulated and down-regulated, respectively, and 47 differentially expressed genes between DB2 and DK, of which 8 and 39 genes were up-regulated and down-regulated. Using real-time PCR, the expression levels of the eight functional genes at different developmental stages of the fruit were also analyzed. These comprehensive analyses showed that both mutants are different from DK, which is the result of natural doubling of ploidy, thereby generating a pleiotropic effect. As we known, it is the first report to study the relationship between bayberry ploidy alterations and genes involved in regulation of fruit mutations, which will help to identify the morphological and cytological characteristics of M. rubra germplasm, and provide a theoretical basis and technical support for genetic improvement and creation of breeding resources.

This study was carried out to unravel the mechanism of reductions in production performances in high stocking densitygeese flocks during summer months in “geese-fish” production system. Experiment 1 observed the water bacterialgrowth, lipopolysaccharde concentrations in water and geese blood, and geese reproductive performances from summerto winter, in two flocks with varying on water stocking densities. Results showed that counts of total bacteria, Escherichiacoli and Salmonella in water, as well as water and geese plasma LPS concentrations, exhibited a tendency decreasing fromthe highest levels in summer, to intermediate levels in autumn, and to the lowest values in winter. Such seasonaldecreases in bacteria and LPS concentrations were associated with similar seasonal decreases in embryo mortality duringincubation. In addition, embryos dead or showing development retardation by day 25 of incubation contained copiousLPS in allantoic fluid, in contrast to the negligible amount in normal developing embryos. Raising on water stockingdensity elevated bacteria counts, LPS concentrations in water and geese plasma, and decreased egg fertility but increasedembryo mortality during incubation. In experiment 2, exogenous LPS treatment to the geese depressed egg laying,reduced egg hatchability, caused sickness behavior in the goslings hatched. In experiment 3, exogenous LPS directlyadministered to day 8 and 18 embryos during incubation dose dependently increased mortality and decreased hatchability,and caused sickness behavior in the goslings hatched. It is concluded that the raising on water geese stocking densitystimulates pathogenic bacteria growth in water, which via LPS contamination impaires embryo development in incubationand therefore reduces geese reproductive performance and gosling quality during the hot summer months.

Synthetic hexaploid wheat (SHW) represents a valuable source of new resistances to a range of biotic and abiotic stresses. A recombinant inbred line (RIL) population with 127 recombinant inbred lines derived from a SHW-derived variety Chuanmai 42 crossing with a Chinese spring wheat variety Chuannong 16 was used to map QTLs for agronomic traits including grain yield, grains per square meter, thousand-kernel weight, spikes per square meter, grain number per spike, grains weight per spike, and biomass yield. The population was genotyped using 184 simple-sequence repeat (SSR) markers and 34 sequence-related amplified polymorphism (SRAP) markers. Of 76 QTLs (LOD>2.5) identified, 42 were found to have a positive effect from Chuanmai 42. The QTL QGy.saas-4D.2 associated with grain yield on chromosome 4D was detected in four of the six environments and the combined analysis, and the mean yield, across six environments, of individuals carrying the Chuanmai 42 allele at this locus was 8.9% higher than that of those lines carrying the Chuannong 16 allele. Seven clusters of the yield-coincident QTLs were detected on 1A, 4A, 3B, 5B, 4D, and 7D.