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51.
Kenneth C. Gross 《Phytochemistry》1983,22(5):1137-1139
Using high-resolution GC, changes in total free galactose, myo-inositol, arabinose, xylose, rhamnose and mannose have been studied in pericarp tiss 相似文献
52.
Summary Two multivariate statistical procedures were used to determine the basic trends of morphologic and geographic variations between
males of a common stored-grain mite,Glycyphagus destructor (Schrank) collected from Canada and Japan. All analyses were carried out on physical measurements of 25 morphological features. Three
principal component analyses bases on the Canadian (50 specimens), Japanese (50 specimens) and the combined populations from
the 2 countries (100 specimens) revealed that the first component, accounting for 40% of the variability in all 3 solutions
represented a measure of the morphologic dimension of the body. The second component, which explained over 18% of the variability,
is a measure of the leg dimension.
Smaller clusters of variates characteristic of the population from each county were also evident. Discriminant analysis, performed
with the Canadian and Japanese populations, identified the variates that differed between the 2 populations and provided an
approximate appraisal of interrelations. The general conclusion based on these analyses is that the Canadian and the Japanese
populations are morphologically distinct. The difference is most evident in the diameters of genu 2, lengths of the sensory
seta WI, lengths of the body, and the distances between the vertical external setae.
Contribution No. 446, from Research Station, Canada Department of Agriculture, Winnipeg, Manitoba, Canada. 相似文献
53.
KABITA ROY 《The Journal of eukaryotic microbiology》1989,36(1):20-23
Morphology and life history of 3 cephaline gregarines found in the gut of the pest of stored fruit, Oryzaephilus mercator. are described. Of these 3, 2 are new species. The 3 species are (1) Hirmocystis minuta (Ishii, 1914) (LP TL = 1:7 – 1:22, WP/WD = 1:1, 6–1:7); (2) Amsotobus indicus n. sp. (LP/TL = 1:3–1:6, WP/WD = 1:1 – 1:1.3); (3) Leidyana oryzaephili n. sp. (LP/TL = 1:2 – 1:12; WP/WD = 1:1–1:1.6). 相似文献
54.
叶龄及树冠不同部位光强对黄花梨光合速率的影响 总被引:7,自引:0,他引:7
笔者以黄花梨为试材,研究了叶龄及树冠不同部位光强对其光合速率的影响。结果表明:黄花梨叶片在展叶后约11天即有少量光合产物输出,25天时,单叶净光合速率接近最大值;密植梨树高光合叶幕厚度约125cm左右。 相似文献
55.
56.
The relationships between indole-3-acetic acid (IAA) diffusing out of the fruit and competition among fruits, and between fruits and shoot tips were investigated using apple ( Malus domestica Borkh. cv. Jonagold) and tomato ( Lycopersicon esculentum Mill.) plants. Dominant fruits always had more diffusible IAA than subordinated, inhibited fruits. Alterations in dominance – by fruit- or shoot tip removal – led to significant changes in diffusible IAA by the remaining fruits. This change could be detected one day after dominance modification.
It is suggested that diffusible IAA is involved in the correlative signal regulating dominance relationship between fruits, and between fruits and shoots in apple and tomato. 相似文献
It is suggested that diffusible IAA is involved in the correlative signal regulating dominance relationship between fruits, and between fruits and shoots in apple and tomato. 相似文献
57.
Hormonal changes associated with fruit set and development in mandarins differing in their parthenocarpic ability 总被引:2,自引:0,他引:2
Satsuma [Citrus unshiu (Mak) Marc.] and Clementine [Citrus reticulata (Hort.) Ex. Tanaka, cv. Oroval] are two related species of seedless mandarins which differ in their tendency to set parthenocarpic fruits. Satsuma fruits naturally set parthenocarpically whereas Clementine mandarins show very low ability to set fruit in the absence of cross-pollination. The endogenous levels of gibberellins (GAs) and free and conjugated indole-acetic acid (IAA) and abscisic acid (ABA) throughout early stages of fruit development were investigated in seedless cultivars of both species. Analyses performed by full-scan combined gas chromatography-mass spectrometry (GC-MS) of extracts from ovaries at anthesis demonstrated the presence of GA19, GA20, GA29, GA1, GA8, GA3 and iso-GA3 in Satsuma mandarin, whereas only GA29, GA3 and trace levels of GA8 were detected in Clementine. At this developmental stage GA-like substances, as estimated by bioassay, reached their highest levels in Satsuma, while Clementine mandarins contained relatively lower levels. In both species the highest levels of free IAA were found at petal-fall stage at which time free ABA levels also peaked. Developing fruits of Clementine had higher amounts of both free IAA and ABA. In Satsuma, levels of conjugated IAA remained low throughout reproductive development whereas in Clementine they increased as the free form declined. In contrast, conjugated ABA was at low levels in Clementine but reached higher concentrations in Satsuma. These results suggest that in these mandarins the potential for setting parthenocarpic fruits is mainly influenced by the hormonal status of the fruit during the later stages of cell division and early stages of cell enlargement. Thus, the condition of low ability to set parthenocarpic fruits appears to be associated with lower levels of active GAs, lower capability to catabolize ABA to conjugated ABA and higher ability to conjugate IAA during this period. 相似文献
58.
Copulatory behavior unrelated to conception is sometimes observed in some non-human primates including the Japanese monkey.
In the present study, the authors examined whether a mature follicle or a newly formed fresh corpus luteum was observed in
the ovaries of female Japanese monkeys which displayed the copulatory behavior unrelated to conception.
Post-conception copulatory behaviors were observed in three out of four females usually kept in individual cages in an air-conditioned
room, and in two out of three females without infants kept in an outdoor group cage. However, neither a mature Graafian follicle
nor a fresh corpus luteum formed newly after conception was observed in any of these females by laparoscopic examinations
conducted immediately after termination of the copulatory behavior. In females with infants born in the preceding birth season,
copulatory behaviors were observed in three out of four females kept in the outdoor group cage, and in two out of four females
in a free-ranging troop. Ovulation was confirmed in one case out of the three kept in the outdoor group cage, but neither
a mature follicle nor a newly formed corpus luteum was observed in the remaining four females.
These findings suggest that copulatory behavior in the Japanese monkey is not always controlled by the development of a follicle
or ovulation in the ovary. 相似文献
59.
Two forms of exopolygalacturonase increase as peach fruits ripen 总被引:1,自引:0,他引:1
Abstract. Freestone peach cultivars are distinguished from clingstone cultivars by a more extensive softening of the mesocarp tissue, and by the separation of mesocarp and endocarp during ripening. Cultivars of both types have been reported to develop exopolygalacturonase activity during ripening, but the enzyme has not been characterized in any detail. During development of freestone peaches ( Prunus persica L. var Coronet), two exopolygalacturonase enzymes were detected 42, 65 and 85 d after full bloom and in ripe fruit. During ripening one enzyme (exoPG 1) increased 36-fold and the other (exoPG 2) 90-fold but exoPG 2 accounted for a 73% of the total activity in ripe fruit. ExoPG 1 was purified 24-fold and exoPG 2 540-fold. ExoPG 2 is a slightly acidic glycoprotein. ExoPG 1 and exoPG 2 differ slightly in their pH optima and in their responses to calcium: each produces monogalacturonic acid as a reaction product. Similar enzymes were found in Flavorerest, a semi-freestone peach. 相似文献
60.
山东省的菌根真菌及分布 总被引:2,自引:0,他引:2
1842年Vittadini观察到树木小根可以从在其上面形成根套的真菌中获得营养。1885年Frank发展和完善了Vittadini 的观察,提出 相似文献