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1.
Kazutaka Kato 《Journal of Forest Research》2008,13(6):386-392
A trial to detect optimal pin-pricking timing in evaluating the ability to form traumatic resin canals (TRCs) of Cryptomeria japonica was examined to select resistant trees to Semanotus japonicus using 14 clones in 2001 and 2002. Resistance to S. japonicus and the ability to form TRCs in the phloem was evaluated by inoculating newly hatched larvae in the bark and by a pin prick,
which was conducted every 10 days (four times) on the trunk around the larval phloem-feeding period, respectively. The larval
survivorship varied greatly among clones for both years. The mean appearance of newly formed TRCs was generally higher in
late treatment for both years, and the tangential width of them was also higher in 2001, whereas those of pre-formed TRCs
were not higher for either year. The larval survivorship did not show significant correlations with the appearance and the
width of pre-formed TRCs on all treatments. However, it showed significant negative correlations with the appearance of newly
formed TRCs on the second and third treatments on the 2-year-old layer, although this was not significant with the width of
them. This suggests that resistant clones might have the mechanism of rapidly forming TRCs when just at the stage of newly
hatched larval entering the phloem. Thus, although the relationship between the appearance and the width of newly formed TRCs
is not clear, pin-pricking treatment when the newly hatched larvae just enter the bark may be one of optimal times for the
evaluation of the resistance of C. japonica to S. japonicus.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
2.
Kazutaka Kato 《Journal of Forest Research》1997,2(2):75-78
To detect developmental differences inEpinotia granitalis in two host tree speciesCryptomeria japonica andChamaecyparis obtusa, the fourth or fifth instar larvae were collected daily from the two species located on the grounds of the National Forest
Tree Breeding Center, from April 19 to May 9 in 1994 and April 18 to May 10 in 1995. Larvae ofE. granitalis collected fromC. obtusa had heavier body weight, developed to larger adults than those collected fromC. japonica, and mortality from the fourth or fifth instar larval stage to adults onC. obtusa was lower than that onC. japonica. All these facts suggest that larval performance onC. obtusa was higher than that onC. japonica. 相似文献
3.
为确定高产脂云南松的早期选择指标,采用石蜡切片法对不同海拔、不同产脂量云南松的针叶、树干韧皮部和木质部的组成性树脂道特征进行解剖观察,结果表明:高产脂与低产脂云南松的针叶树脂道个数、树干木质部树脂道密度、韧皮部树脂道大小及单位长度树脂道数量存在极显著差异(P＜0.01),但不同海拔之间无显著差异;高、低海拔高产脂云南松针叶树脂道数量分别比低产脂的高38.89％、30.34％,树干木质部树脂道密度分别高58.06％、48.48％,韧皮部树脂道大小分别高32.20％、29.73％,韧皮部单位长度树脂道数量分别高21.95％、38.51％.说明针叶树脂道数量、树干木质部树脂道密度及韧皮部树脂道大小3项指标,也可作为云南松产脂力评价的部分指标. 相似文献
4.
G. Georgiev 《Journal of pest science》2005,78(3):161-165
The major bioecological characteristics of Bracon intercessor Nees (Hymenoptera: Braconidae), a parasitoid of the poplar clearwing moth, Paranthrene tabaniformis (Rott.) (Lepidoptera: Sesiidae), were studied from 1987 to 2003. Poplar shoots infested with P. tabaniformis larvae were collected in 11 localities in Bulgaria and examined in the laboratory, and infestations were also studied in the field. B. intercessor was recorded in seven localities and was found to be a gregarious external larval parasitoid of P. tabaniformis. Two generations of the parasitoid developed on the host. The first (summer) generation was associated with early and mid-stage (up to third instar) host larvae, and the second (overwintering) generation with third- to fifth-instar larvae. The average number of parasitoid individuals feeding on a host was 4.5 and 12.4 in summer and overwintering generations, respectively. The maximum number recorded was 25 individuals per host in the overwintering generation. B. intercessor overwintered as a mature larva on the host and completed its development in early spring. The adults from the overwintering generation appeared in April, about 1 month prior to emergence of P. tabaniformis. The life cycle of B. intercessor was not in close synchrony with the development of P. tabaniformis in the spring, but the parasitoid adults which fed on honey-sugar solution lived for up to 31 days (males) and 86 days (females), respectively. This suggests that, in the field, B. intercessor females eclosing in the spring could survive until the host larvae appear if nectar is available. Adults of the summer generation emerge from July to September when sufficient suitable host larvae are available. B. intercessor was responsible for 1.5% of the average mortality of the P. tabaniformis overwintering larvae. The host mortality caused by the summer generation of the parasitoid ranged from 3.2% to 5.8%. 相似文献
5.
Tadahisa Urano 《Journal of Forest Research》2013,18(2):159-167
Release experiments of Doryctes yogoi Watanabe onto Semanotus japonicus Lacordaire larvae inoculated into Japanese cedar, Cryptomeria japonica D. Don, were conducted to clarify the role of the parasitoids in the mortality of S. japonicus and the efficiency of the parasitoid as a natural enemy of the beetle. S. japonicus larvae were inoculated into three types of samples: live trees, girdled trees, and logs, each of which was treated in three ways: D. yogoi was released into the sample, the sample was screened (excluding natural enemies), or the sample was used as a control. In live trees, more than 90% of the larvae were killed by resin flow, and the percentage of parasitism by D. yogoi was less than 6%. In girdled trees, most of the larvae were dead due to the resin in the trees, having survived inoculation as well as in live trees, but many larvae were parasitized by D. yogoi in dead trees like logs. The present study revealed three negative effects of resin flow on parasitism by D. yogoi in the live trees. First, most of the host larvae died before reaching a size suitable for parasitism. Second, parasitoid larvae were caught in the resin with their hosts and died. Third, the host-searching and oviposition of female D. yogoi were obstructed by resin flow on the surface of the trunk. The efficiency of D. yogoi as a natural enemy of S. japonicus is discussed. 相似文献
6.
[目的]松材线虫病是我国对森林危害和威胁最严重的病害,控制其传播媒介昆虫松褐天牛是防治松材线虫病的主要手段。作者发现的松褐天牛深沟茧蜂(Iphiaulax monochamusi Yang)是寄生松褐天牛中老龄幼虫的重要天敌。为明确松褐天牛深沟茧蜂的寄生率与寄主树木、寄主和环境因子的关系,开展了本研究。[方法]通过解剖46株松褐天牛危害致死的马尾松,调查了松褐天牛深沟茧蜂寄生率与马尾松、松褐天牛和环境因子之间的关系。[结果]调查研究表明:寄主树木的高度、胸径和树龄对松褐天牛深沟茧蜂寄生率没有显著影响,松褐天牛的数量对松褐天牛深沟茧蜂寄生率亦没有显著影响,而松褐天牛幼虫龄期和松褐天牛幼虫在树干上的位置显著影响松褐天牛深沟茧蜂寄生率。松褐天牛深沟茧蜂寄生率与松褐天牛龄期呈显著正相关,其偏好寄生3~5龄幼虫;就天牛在其危害寄主树木上的位置而言,松褐天牛深沟茧蜂偏好寄生马尾松主干上部和在韧皮部危害的松褐天牛幼虫,其对位于马尾松树干上部的寄主幼虫寄生率最高,达27.38%,对在韧皮部生活、危害的寄主幼虫寄生率为20.18%,显著高于位于木质部生活的寄主幼虫寄生率(5.46%)。逐步回归分析表明:影响松褐天牛深沟茧蜂寄生率的关键环境因子是寄主树木的坡位和其它天敌寄生率,其中,坡位与松褐天牛深沟茧蜂呈显著正相关,其它天敌寄生率与松褐天牛深沟茧蜂寄生率呈显著负相关。[结论]以上研究初步明确了松褐天牛深沟茧蜂的寄生率与寄主树木、寄主害虫和天敌之间的关系,为今后利用该重要天敌控制松褐天牛打下了基础。 相似文献
7.
Cistella japonica was inoculated onto the stems of youngChamaecyparis obtusa trees, and the development of external and internal symptoms was investigated for five years. Most lesions started exuding
resin from May to July during the first growing season after inoculation, while a few lesions started exuding resin during
the second growing season. Resin exudation lasted for two successive years on most lesions, and during successive three, four,
or five years on some lesions. Resin exuded excessively in the secondary phloem of the lesions and resin cysts frequently
developed there. The lesions where cambial tissue was necrosed occupied 18% of all the lesions and the resinous areas expanded
to a larger size than those where resin simply exuded in the phloem.Ci. japonica was reisolated from some inoculated lesion tissues at a high frequency. The isolation frequency of the fungus from some lesion
tissues two and more years later was zero or low and that ofCryptosporiopsis abietina was high.
This work was supported by a grant from the Forest Agency of the Japanese Government. 相似文献
8.
To determine whether Monochamus alternatus can use the Japanese cedar (Cryptomeria japonica) as a host tree, experiments were conducted in a laboratory using three insect populations of different localities. Adult
females chose Pinus densiflora bolts as oviposition substrate when supplied with cedar and pine bolts simultaneously, whereas some females from one locality
oviposited on cedar bolts when supplied with them exclusively. Seventy-three percent of 40 eggs hatched in cedar bolts. When
the first instar larvae were inoculated on cedar bolts, the development was stunted greatly and all died during the larval
stage. Two of 20 larvae that were inoculated on cedar bolts at the third instar entered the diapause and one larva developed
into an adult female, which produced viable eggs but was much smaller than those obtained from pine bolts. The results did
not exclude the possibility that M. alternatus can use recently killed C. japonica trees as a host. 相似文献
9.
Casmara patrona is one of the main borer pests damaging Camellia oleifera in China. Few reports about this insect were published. The life history, biological characteristics and natural enemies of C. patrona were investigated through field survey and laboratory observation in this study. The results showed that C. patrona had one generation in one year or two years, and overwintered as 3rd-5th instar larva in Zhejiang Province. About 88 percent of larvae began to pupate in early May, and the rest kept feeding till the next year. The adults could be observed from early June to early July, and the peak of emergence occurred in late June. The adults began to oviposit in late June and terminated in early July. The eggs started hatching in early July, and then the larvae bored into the branch to feed. The entrance holes of the larvae distributed predominately in the middle of the eastern and southern part of C. oleifera tree. The larva had five instars, and there were 10-50 days when the larva did not feed between consecutive instars. 相似文献
10.
Parasitism by parasitoid wasps on the larvae of Epinotia granitalis (Butler), which is a wood-injuring pest in coniferous plantations, was observed for 6 years in two plantation forests of
Chamaecyparis obtusa (Sieb. et Zucc.) Endl. and Cryptomeria japonica (L.f.) D. Don that were adjacent to each other and consisted of trees of almost the same size. E. granitalis larvae were collected from early April to mid-May, then reared in glass bottles, and finally examined to determine whether
or not the larvae had been parasitized. Five species of parasitoids were recorded; two of them were classified in Ichneumonidae,
Campoplex spp. A and B, and others in Braconidae, Iconella repleta Papp, Bassus cingulipes Nees von Esenbeck, and Bracon spp. In all 6 years, parasitism was first observed around 20 April. Species composition of parasitoids differed greatly among
years and between forests. In 1 year in each forest the percentage parasitism increased significantly with the sampling date,
indicating that not all parasitoids attack the same developmental stage of E. granitalis. The mean percentage parasitism per year was significantly higher in the forest of C. obtusa [11.5(%) ± 5.7(SD)] than in the forest of C. japonica (3.0 ± 4.1). These results suggest that the efficiency of parasitoid adults in finding hosts differed between the two forests.
Received: September 20, 2001 / Accepted: August 5, 2002
Acknowledgments We are grateful to Dr. K. Maeto, Shikoku Research Center, Forestry and Forest Products Research Institute, and to Dr. K.
Konishi, National Agricultural Research Center for Hokkaido Region, for identifying parasitoids, and to Dr. T. Miyaura, Forest
Tree Breeding Center, and Dr. H. Kosaka, Forestry and Forest Products Research Institute, for their helpful advice throughout
the study.
Correspondence to:K. Kato 相似文献
11.
Yasuo Suto 《Journal of Forest Research》1998,3(2):99-102
In the resinous lesion development caused by the inoculation withCistella japonica onChamaecyparis obtusa stem, numerous traumatic resin-canals were formed at certain radial intervals in the secondary phloem. These formation started
in the ring grown in the current or the previous year of inoculation and the resin-canals were subsequently formed in the
newly grown rings. The resin-canals were arranged in tangential series in one to two lines in an annual-ring. Artificially
induced resin-canal formation was similar to that in naturally infected resinous stem canker. The results from the present
study reconfirmed thatCi. japonica is the causal agent of the disease. 相似文献
12.
Ephestia kuehniella adults were stored at 10°C for 1–10 weeks. Reproductive ability and number of living adults decreased depending on the length
of the storage period. Long-term exposure to cold lengthened the life of the adults and 50% mortality was reached after 6 weeks.
To obtain complete mortality and sterility 10 weeks of storage was needed. The larvae reared on corn flour diet developed
to the adult stage more rapidly than that of the other treatments. The adults reared on oat flour produced significantly more
eggs than the other diets. There was no difference among diets with regard to emergence rate, longevity or sex ration of E. kuehniella adults. Trichogramma evanescens did not differentiate among hosts from different food sources with respect to parasitization, adult emergence and sex ratio.
The suitability of the eggs from cold-exposed adults with respect to parasitization was found to be the same as the control
during the first 3 weeks. 相似文献
13.
Shi-xiang Zong You-qing Luo Ya-qin Cui Jian-wei Wang Wei Yan Ai-jie Liu Heliövaara Kari 《中国林学(英文版)》2009,11(1):24-27
The population density and distribution of the three major boring pests, Holcocerus artemisiae, Sphenoptera sp. and Adosopius sp. were studied in their host plant Artemisia ordosica. Results show that the larvae of H. artemisiae mainly bore the rhizome of A. ordosica, but also the larvae of Sphenoptera sp. and Adosopius sp. bore the rhizome of A. tordosica. The adults of Sphenoptera sp. and Adosopius sp. feed on the leaves of A. ordosica as a nutritional supplement. The distribution of the larvae of three pests in their host plant is completely different. H. artemisiae and Sphenoptera sp. are distributed in the whole A. ordosica plant. The newly hatched larvae first feed on the phloem and xylem of stem and then burrow to the roots before the winter
of the same year. However, Adosopius sp. is distributed mainly in the roots. The newly hatched larvae move from the phloem to the xylem, and gradually damage
the lower part of the trunk. The larvae of the three pests sometimes coexist in a single A. ordosica plant. However, the probability of the coexistence of the three pests is very small. The highest probability of coexistence
of two pests was observed in Sphenoptera sp. and H. artemisiae, while the probability of coexistence of Sphenoptera sp. and Adosopius sp. as well as H. artemisiae and Adosopius sp. was smaller. The reasons for coexistence or its avoidance are not only related to the amount of food provided nor the
volume of larval living space in a single A. ordosica plant, but also related to the development characteristics of different kinds of larvae and interspecific competition. 相似文献
14.
Pittosporum tobira L. (Family Pittosporaceae) is an important plant species grown in parks and gardens in Turkey. The cottony cushion scale, Icerya purchasi Maskell (Homoptera: Coccina, Margarodidae), is an important pest of P. tobira, and causes damage mainly to the leaves, branches and stems of the host plant. In spite of the great economic importance of I. purchasi to its host plant P. tobira, information has been limited on some basic anatomical parameters of the nature of the damage to leaves and branches. The present study was, therefore, initiated to investigate the insertion and penetration of stylets into the leaves and branches of P. tobira, the length of stylets and depth of penetration in both of these tissues, and penetration of stylets into the cortex, xylem and phloem tissues and into the secretory and non-secretory canals of the leaves and branches. The results showed great variations between the leaves and branches in all the criteria observed in I. purchasi infesting P. tobira. The study found 20 whole and 23 broken mouthparts in the leaves as compared to 3 whole mouthparts and 1 broken in the branches. Length of the stylets inserted into the leaves ranged from 33.83 m to 540.93 m and into the branches from 202.85 m to 340.8 m. The stylets reached greater depths in the leaves, at 540.93 m, as compared to 498.67 m in the branches. The stylets in the leaves were associated with 12 secretory canals, but with none in the branches. It was found that three stylets reached xylem in the leaves as compared to one in the branches. Similarly, 17 stylets in the leaves reached to the phloem, but only 2 in the branches. No stylets were found in the cortex of the leaves, but one was found in the branches. In the leaves, 11 stylets reached and remained in the non-secretory canals, but none in the case of the branches. 相似文献
15.
试验研究了饲毒龄期、饲毒浓度对舞毒蛾存活、幼虫体质量、虫尸质量和含毒量的影响以及饲毒时间对舞毒蛾含毒量的影响.结果表明:饲毒龄期和饲毒浓度对幼虫存活率和体质量增长均有不同程度的影响,饲毒龄期越小、饲毒浓度越高,死亡时间越早,死亡率越高,体质量增长越缓慢;而且饲毒时龄期越小、饲毒浓度越高,虫尸质量也越小,其含毒量也越低.饲毒时间与含毒量成抛物线型,饲毒时间过短或过长,体内含毒量均较低.由于5龄幼虫饲毒后有78％以上个体发育至蛹期,不发生死亡现象,因此,室内增殖舞毒蛾核型多角体病毒时,应选取4龄初幼虫喂饲1.0×106 PIB·mL-1病毒为宜,接毒10d后开始收集饲毒幼虫. 相似文献
16.
The parasitoid complex of Saperda populnea (L.) (Col., Cerambycidae) was studied during the period 2002–2003 at different sites in Bulgaria. Galls containing cerambycid larvae were collected on branches of aspen (Populus tremula L.), goat willow (Salix caprea L.) and hybrid poplars and were studied under laboratory conditions. As a result, four new species for the parasitoid complex of S. populnea in Bulgaria were recorded: Dolichomitus tuberculatus (Geoffroy), Xylophrurus lancifer (Gravenhorst), Gelis ornatulus (Thomson) (Hym., Ichneumonidae) and Dendrocerus serricornis (Boheman) (Hym., Megaspilidae). D. serricornis and G. ornatulus are new species for Bulgarian fauna. D. tuberculatus and X. lancifer were found as primary parasitoids, and G. ornatulus and D. serricornis as hyperparasitoids. The primary parasitoids developed solitarily in the host larvae. D. serricornis was reared gregariously from a puparium of Billaea irrorata (Meig.) (Dipt., Tachinidae). The host of G. ornatulus was not identified, but the hyperparasitid could be connected with Iphiaulax impostor (Scop.) (Hym., Braconidae). The mortality of S. populnea caused by the parasitoids was 2.0–6.3%. 相似文献
17.
In anAbies homolepis Sieb. et Zucc. forest at Matsumoto, Nagano Pref., cumulative damage byXylotrechus villioni (Villard) (Coleoptera: Cerambycidae) was observed on tree branches. Of the 14 major branches in one sample tree, six had
cumulative damage by boring larvae, of which 3 had been bored by multiple larvae. No adult emergence holes were found on the
whole tree, suggesting very low survivorship from boring larva to emerging adult. Galleries made by single larvae were often
observed to be terminated by a depression apparently carved by a picid woodpecker, suggesting that they are important predators
of the cerambycid. The manner of cicatrix formation with phloem tissue over the larval gallery in anAbies veitchii Lindl. branch at Mt. Fuji, Yamanashi Pref. is presented.
Studies onXylotrechus villioni (Villard) (Coleoptera: Cerambycidae), a primary borer of coniferous trees in Japan (III). This work was presented at the
104th Annual Meeting of Japanese Forestry Society at Morioka (April, 1993) and 20th International Congress of Entomology at
Firenze (August, 1996).
This work is supported by a Grant-in-Aid for Scientific Research (No.02660163) from the Ministry of Education, Science, Sports,
and Culture of Japan. 相似文献
18.
Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), (= A. marcopoli Obenberger), is an important bark beetle attacking ash trees (Fraxinus spp.). It is very difficult to detect and control because of its highly concealed life history. This pest mainly distributed
in partial Asian countries (China, Japan, Korea, Mongolia) and Far East Russia, while in China it presented in Heilongjiang,
Jilin, Liaoning, Shandong, Inner Mongolia, Hebei, Taiwan Provinces and Tianjin City, etc. The important timber species F. mandshurica and gardening tree F. velutina were damaged severely in northern China. Spathius agrili Yang (Hymenoptera: Braconidae) is an important ectoparasitic wasp of the EAB larvae. This parasitoid has the potential to
use as an excellent biological control agent for suppressing populations of EAB. The differences of emergence date between
overwintered S. agrili and its host, parasitism rates at different periods, relations between parasitism rates and host densities, and relationships
between ovipositions of braconid wasp and body sizes of host larvae were studied using methods of regular surveys in forests
and observations in laboratory. Results revealed that the emergence of S. agrili was more than one month later than that of its host. It suggests good synchrony between parasitoid emergence and host availability.
The overwintered S. agrili emerged from mid June to mid August with the peak in July in 2003, and it lasted from late May till late July with the peak
during late June to early July in 2004. While the EAB emergence period ranged from mid May to late May in 2003, it ranged
from mid April to mid May in 2004 (in laboratory). The emergence date of parasitoid asynchronously inosculated with the optimum
developmental instars of the earliest host larvae, which was the result of a long-term co-evolution between the two species.
It was also suggested that the parasitoid S. agrili could be a specialized natural enemy for EAB. The natural parasitism rates on the whole gradually increased in field with
time. The body sizes of host larvae, i.e. larval instar, affected the decision of parasitoid S. agrili to lay eggs or not. Under natural conditions, this parasitoid usually oviposited only on those host larvae with a prontum
and body width more than 1.5 mm, and a body length in excess of 12 mm, i.e. the third or fourth instar larvae. These findings
would consequentially contribute to the further successfully biological control of the trunk borer.
__________
Translated from Acta Ecologica Sinica, 2006, 26(4): 1,103–1,109 [译自: 生态学报] 相似文献
19.
Seyed Ali Asghar Fathi 《Journal of pest science》2009,82(3):267-272
Two-spotted spider mite (TSSM) and onion thrips are serious pests of potatoes in the Ardabil region (Iran). In the present
study, anthocorid species were identified in potato fields of this region during 2006 and 2007. The results of the abundance
study indicate that Orius niger (Wolff) and O. minutus (Linnaeus) are major predators of these pests in potato fields. The life table parameters of these predators were compared
when they were fed 2nd instar larvae of onion thrips or female TSSM on potato leaves. In these experiments, O. niger had a lower nymphal mortality, longer oviposition period, higher net reproductive rate (R
0), and higher intrinsic rate of natural increase (r
m
) when fed thrips instead of mites. O. minutus feeding on mites compare to thrips had a lower nymphal mortality, longer oviposition period, higher net reproductive rate,
and higher intrinsic rate of natural increase. Based on these results, it can be concluded that these predators could be useful
as biological agents in potato fields. 相似文献
20.
The entomophagous Serangium parcesetosum Sicard (Col., Coccinellidae) is an effective predator of some whitefly species. However, information on the influence of the preys host plant species on its biological and ecological characteristics is still lacking in the literature. Therefore, the current study focuses on the possible influence of three greenhouse and two field host plant species of Bemisia tabaci (Genn.) (Hom., Aleyrodidae) on the number of eggs laid by S. parcesetosum. In addition, because of the economic importance and widespread planting of cucumber in greenhouses and cotton in the field, these plants were selected for further investigation into the development, mortality, longevity and reproduction of S. parcesetosum at a high temperature in the laboratory. Results showed that S. parcesetosum was able to lay eggs on all five host plant species of B. tabaci, whether greenhouse or field plants. However, among the three greenhouse plant species studied, S. parcesetosum females laid the highest number of eggs on cucumber followed by tomato and then sweet pepper. Of the two field plant species, significantly higher numbers of eggs were laid on tobacco than on cotton. S. parcesetosum could develop either on cucumber or on cotton as preferable host plant species for B. tabaci. There were significant differences in mean developmental duration of larval instars of the same sex between both host plant species; the duration was significantly shorter on cucumber than on cotton. There were no significant differences for mean total developmental duration from egg to adult emergence between both host plant species within the same sex; females showed a mean of 15.9 days and males of 15.1 days on cucumber, while on cotton the means were 17.2 days for females and 16.2 days for males. Total mortality percentage of S. parcesetosum during development from egg to adult stage was lower on cucumber than on cotton, 20.6 and 23.8%, respectively. Longevity of S. parcesetosum varied according to host plant species and sex with a mean of 63.4 days for females and 50.3 days for males on cucumber, and 92.4 days for females and 52.5 days for males on cotton. On cucumber, mean period of oviposition of S. parcesetosum was significantly longer than on cotton. Mean total fecundity was significantly higher on cucumber than on cotton, with means of 97.7 and 31.0 eggs/female, respectively. 相似文献