Influence of the Parasite Pilostyles ingae (Rafflesiaceae) on some Physiological Parameters of the Host Plant,Mimosa naguirei (Mimosaceae)*

plants found at this site were densely covered by flowers of the parasite on their stems indicating heavy development of cellular The holoparasite/host interaction of Pilostyles ingae (Karst.) Hook. f. (Rafflesiaceae) and Mimosa naguirei Barneby (Mimosaceae) was studied in the open campo rupestre vegetation of Serra do Cipó (State of Minas Gerais, Brazil). Infected M. naguirei threads of the parasite in the bark of the hosts. Cellular threads of the parasite are likely to be richer in lipids and hence depleted in ¹³C. This may explain the significantly more negative carbon isotope ratios (δ¹³C values) of the bark of infected host plants observed as compared to other tissues of infected and non-infected host plants. Photosynthetic parameters such as potential quantum yield of photosystem II (F_v/F_m), apparent photosynthetic electron transport rates (ETR) and effective quantum yield of photosystem II (A F/F'_m) in light dependence curves, as well as δ¹³C values of leaves as a relative measure of average intercellular CO₂ partial pressure during photosynthesis over the lifetime of the leaves, which is also related to average stomatal conductance via water use efficiency, were remarkably similar. This suggests a well balanced relation between the Mimosa host and the Pilostyles parasite, in contrast to other hemiparasitic angiosperm parasite/host interactions where the parasite (e.g. Striga) is known to have strong detrimental effects on host photosynthesis.     

Effects of Number of Photoperiodic Cycles on Induction and Development of Flowers and Fruits in Corchorus olitorius L. (var. oniyaya Epen.)

Plants of Corchorus olitorius, a short-day plant, were subjectedto varying numbers of short-day cycles before transfer to longdays. Treatments started after germination of the seeds at thetime of cotyledon release. Four short-day cycles (10 h naturaldaylight followed by 14 h darkness) were sufficient to induceflowering in all plants. The number of flowers and fruits producedon a plant increased as the number of short-day cycles was increasedfrom three to 30. Plants given three to seven short-day cyclesproduced flowers on the main stem only but when plants weremaintained in short days for longer periods, flowers were alsoproduced on the branches. The growth in d. wt of fruits wasgreatest when plants were maintained in short days throughout. Corchorus olitorius L., flowering, fruit development, photoperiodism     

Effect of Number of Photoperiodic Cycles on Flowering and Fruiting in Early and Late Varieties of Okra (Abelmoschus esculentus (L.) Moench.)

Early and late varieties of the short day plant, Abelmoschusesculentus (L.) Moench. (= Hibiscus esculentus L.), were subjectedto various numbers of short days (SD; 10 h natural daylight)before transfer to 16 h long days. Short day treatments werestarted at the time of cotyledon release following seed germination,and their effects on the induction and development of flowersand fruits were recorded. While early okra required 6 SD cyclesfor the induction of flowering in all plants, late okra required14. However, both varieties needed more than 20 SD cycles forflower opening; flower buds produced by plants given fewer SDcycles abscinded with little or no development. In both varieties,the number of flower buds produced on each plant increased asthe number of short day cycles was increased from 5 to 20; flowerbuds were initiated at more axillary bud sites on the main stem.Three fruits were formed on each plant of both varieties subjectedto more than 30 SD cycles but, while the last formed fruit abscindedwithout development, the other two developed and became filledwith seeds. However, the greatest yield in fruit dry weightwas from plants kept under SD throughout and also in late okraplants given 55 SD. In general, the total number of seeds perplant increased as a larger number of SD cycles were imposed.     

Mineral Nutrition of Sandalwood (Santalum spicatum)

Acacia acuminata is a preferred host of the root hemiparasitictree, Santalum spicatum (sandalwood). Comparison between nutrientcontent of adult trees of sandalwood and results for an earlierstudy of the mistletoe, Amyema preissii, on the same host species,A. acuminata, showed similar high levels of K and Na and lowlevels of Zn in both parasites compared with the host plants.Differences in K, Ca, N and Cu levels between parasitized anduninfected Acacias imply that the host plant contributes tothe nutrition of sandalwood. The high K/Ca ratio in sandalwoodconfirms that K uptake in preference to Ca is a general featureof all categories of angiosperm parasites. Patterns of distribution of nutrients between various partsof sandalwood and A. acuminata depend on the type of nutrient,but levels are usually highest in leaves of both species andthe haustoria. Although K, Ca and Na are much lower in the kernelsthan in vegetative parts of the parasite, only seedlings withoutsupplementary Ca in a nutrient omission experiment failed togrow at all in the absence of hosts. Growth is not dependenton the level of K in the unattached plants but other evidenceindicates it may have a role in water uptake in the attachedplant. Calcium supply has a marked effect on internal Ca levelsand growth of unattached plants. Compared with field plants,levels of Ca, and to a lesser extent Zn, were much higher inplants of the Ca/K treatment that produced greatest growth over34 weeks. Haustorial formation is enhanced by the presence of A. acuminataroots. However, competition for nutrients, especially Ca, fromco-planted A. acuminata seedlings results in suppression ofgrowth of young sandalwood compared with their growth in theabsence of the host species. Key words: Mineral nutrients, Santalum spicatum, Acacia acuminata, hemiparasites, K/Ca nutrition, seeds     

Predation potential of the earwig Euborellia annulipes on fruit fly larvae and trophic interactions with the parasitoid Diachasmimorpha longicaudata

The earwig Euborellia annulipes (Lucas) (Dermaptera: Anisolabididae), a generalist predator, has been observed in fruits infested with fruit fly larvae, which are frequently parasitized by parasitoid wasps. Neither the capacity of earwigs to predate on fruit flies nor intraguild interactions between earwigs and fruit fly parasitoids have been investigated. Here, we studied in laboratory conditions the predation on the fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) by the earwig E. annulipes, and whether parasitism of fruit fly larvae by the parasitoid wasp Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) influences predation by the earwig. We evaluated the predation capacity, functional response and prey preference of E. annulipes for parasitized and non-parasitized fruit fly larvae in choice and no-choice tests. We found that earwigs prey on second- and third-instar larvae and pupae of C. capitata and consumed larger numbers of second-instar larvae, followed by third-instar larvae and pupae. Females prey on larger numbers of fruit flies than did males, regardless of the prey developmental stage, but both sexes exhibited a type II functional response. Interestingly, males killed but did not consume fruit fly larvae more than did females. In no-choice tests, earwig females consumed equal numbers of parasitized and non-parasitized fruit fly larvae. However, in choice tests, the females avoided feeding on parasitized larvae. Subsequent tests with hexane-washed parasitized and non-parasitized larvae showed that putative chemical markings left on fruit flies by parasitoids did not drive the earwig preference towards non-parasitized larvae. These findings suggest that E. annulipes is a potential biological control agent for C. capitata, and that, because the earwig avoids consuming larvae parasitized by D. longicaudata, a combination of the two natural enemies could have an additive effect on pest mortality.     

A Physiological Analysis of the Branching Pattern in Sequential Types of Groundnut in Relation to the Fruiting Nodes and the Total Mature Pods Produced

The branching pattern of eight sequential branching types ofgroundnut was studied and the contribution of each node (fruitingpoint) of the n, n+1 and n+2 branches (if present) to the totalnumber of mature pods per plant ascertained. The results indicatedthat n+2 branches were present in several varieties and theircontribution to mature pods was significant in some of them.The first three nodes of the n+1 branches contributed from 50.6per cent (in a variety which had significantly more n+2 branches)to 88 per cent in other varieties. The results also indicatedthat the contribution of the late formed n+1 branches was lowand the total mature pods produced from all nodes decreasedwith each successive (chronologically) n+1 branch in all thevarieties studied. Neither the total number of n+1 branchesnor the number of mature pods per node was related to the podnumber or pod yield, but the total number of fruiting pointsfrom all branches showed a high correlation with pod yield andmature pod number at harvest. The results suggest that for higherpod yield it may be desirable to have only a few n+1 branches(4 or 5) but with more fruiting points on each branch. Arachis hypogaea, branching pattern, sequential types, fruiting points     

Seed predation of Copaifera langsdorffii (Fabaceae): a tropical tree with supra‐annual fruiting

Seed predation is an important ecological and evolutionary force that directly affects the distribution of plant species. Copaifera langsdorffii is a tropical tree species with supra‐annual fruiting, which has its seeds predated by a specialist endogenous insect (Rynochenus brevicollis: Curculionidae) in the Brazilian savanna. Three hypotheses were addressed: (i) the predator satiation hypothesis, (ii) the resource concentration hypothesis and (iii) the larger seed predation hypothesis. A total of 112 individual C. langsdorffii were monitored monthly from January to August during four consecutive years (from 2008 to 2011) to determine the presence of fruits on each plant. All trees produced fruits in the year 2008, whereas none of them produced flowers or fruits in 2009 or 2010. Moreover, only 65 individuals (58%) marked in 2008 produced fruits in 2011. The number of fruits per plant was approximately 21% greater in 2008 than in 2011, while the percentage of seed predation was 76% greater in 2011, thereby supporting the predator satiation hypothesis. The percentage of seeds predated was not affected by the number of fruits per plant. Therefore, our data did not support the resource concentration hypothesis. Plants producing large seeds experienced more seed predation by R. brevicollis, supporting the larger seed predation hypothesis. In addition, we also observed a positive relationship between seed volume and adult R. brevicollis weight. This study demonstrates the importance of supra‐annual fruiting for increasing survivorship of C. langsdorffii seeds both at the individual and the population level, and suggests that seed predators select plants producing large seeds as a way of increasing the number of offspring.     

The holoparasitic endophyte Bdallophyton americanum affects root water conductivity of the tree Bursera simaruba

It has been reported that parasitic vascular plants (hemiparasites and holoparasites) may affect host fitness, but the effects produced by root endophyte holoparasitic species on its host have not been documented. Here the effect of the holoparasitic endophyte Bdallophyton americanum (R. Br.) Harms on the root conductivity of Bursera simaruba (L.) Sarg. was studied. Parasitized and non-parasitized root segments were sampled in the rainy and dry seasons in a dry coastal forest in central Veracruz, Mexico. Root diameter, hydraulic (K _h) and specific conductivity (K _s = K _h/root transverse area), percent loss of conductivity and reproductive specific conductivity (K _h /inflorescence or infructescense dry weight) data were obtained. The diameter and number of conductive and non-conductive vessels were recorded in parasitized and non-parasitized root segments in the dry season. Root diameters were not different between root types and seasons, but root specific conductivity was different both between seasons and root types. Specific conductivity on parasitized roots was 61% (wet season) and 85% (dry season) lower than that recorded for non-parasitized roots in the wet season. Root hydraulic conductivity was positively related with the biomass of reproductive structures of B. americanum in the wet season. The parasite appears to alter the xylem morphogenesis of the host, reducing vessel number by 40%, but not plugging or otherwise harming the conductive vessels, and resulted in no change in vessel diameter. Contrary to what has been reported to occur in some plant stems infected with hemiparasitic mistletoes, B. americanum decreases but does not eliminate conductivity to the distal plant parts.     

寄主对桔小实蝇耐寒性的影响

为了研究寄主营养对桔小实蝇耐寒性的作用,测定了以15种果蔬饲养的桔小实蝇1日龄蛹的过冷却点(supercooling points,SCP); 再选取南瓜、西红柿、柑桔、番石榴和杨桃等5种果蔬,测定了桔小实蝇3龄老熟幼虫、1日龄蛹、3日龄蛹、5日龄蛹、7日龄蛹和雌雄成虫的过冷却点,并观察了1日龄蛹的低温存活力。结果表明：（1）15种果蔬饲养所得的桔小实蝇1日龄蛹SCP均值在-11.03℃～-13.17℃,不同寄主发育的桔小实蝇SCP值存在显著性差异,其中以取食蒲桃的最高,为-11.03℃,取食苦瓜的最低,为-13.17℃。（2）5种果蔬饲养所得的桔小实蝇各虫态的SCP均值存在极显著差异(F_(4,863)＝35.6,P<0.01); 同一寄主上的桔小实蝇不同虫态之间SCP均值也达到极显著性差异(F_(6,863)＝392.9,P<0.01); 且寄主和发育龄期之间存在着极显著的交互作用(F_(24,863)＝9.4,P<0.01)。（3）桔小实蝇各发育阶段,SCP值表现一定变化： 老熟幼虫发育至1日龄蛹,SCP值变化不大; 蛹发育至3、5和7天过冷却能力明显增强,降至-20℃左右,但他们之间没有明显区别; 羽化后3～5天的成虫SCP值又升高至-10℃左右。老熟幼虫、1日龄蛹和2～3日龄成虫与3日龄、5日龄和7日龄蛹的SCP值之间有显著性差异。（4）将5种果蔬饲养所得的桔小实蝇1日龄蛹置于6℃和-3℃下进行较长时间(1～8天)和较短时间(1～8 h)的低温处理,发现番石榴、杨桃和南瓜发育的蛹经低温处理后的校正羽化率较西红柿和柑桔发育的蛹高; 同样在0℃、3℃、6℃和9℃处理(2天)的实验中,得出相似的结果。因此,本实验结果表明桔小实蝇幼虫由于生活寄主的不同使得其下一代蛹的耐寒性产生了差异,引起其差异的原因值得进一步研究。     

Three new species of Mimosa sect. Mimosa (Leguminosae,Mimosoideae) from the campos rupestres of Minas Gerais,Brazil

Three new species of Mimosa sect. Mimosa ser. Mimosa subser. Polycephalae (Leguminosae, Mimosoideae) are described and illustrated. Mimosa canastrensis, Mimosa chrysothrix, and Mimosa decumbens are all from the campos rupestres of Minas Gerais, Brazil. Discussions about the distributions, habitat, and phenology of the species are provided, in addition to comparisons with similar taxa.     

Morphological observations on the preimaginal stages ofAphelinus varipes (Hym., Aphelinidae) and the effects of this parasitoid on the aphidRhopalosiphum padi (Hom., Aphididae)

Three instar larvae could be observed forAphelinus varipes. In the second and third instars, the colon which forms the largest part of the hindgut was composed of secretory cells. There was a reduction in the size and number of embryos produced by parasitized aphids. Fat cells of parasitized aphids also degenerated sooner than those of unparasitized aphids. The number of mycetocytes remained higher in parasitizedRhopalosiphum padi than in non-parasitized aphids. During the last instar ofA. varipes the host aphid developed into a mummy in which black pigments were incorporated into the exocuticle and the integument of the aphid became sclerotized.     

Effects of a parasitic nematode on male mate choice in a livebearing fish with a coercive mating system (western mosquitofish, Gambusia affinis)

I examined the effects of the parasitic larval nematode, Eustrongylides ignotus, on male mate choice in the western mosquitofish, Gambusia affinis. I hypothesized that parasite presence influences male mate choice either directly (via reduction in male mating behavior due to presence of parasite in females) or indirectly (via reduction in male mating behavior due to reduced condition of infected females). Specifically, I tested the predictions that (1) males would mate preferentially with uninfected over infected females (scoring both mating attempts and association time with females); (2) parasitized females would be in poorer condition than non-parasitized females (measured as soluble fat stores); and (3) parasitized females would have reduced fecundity (measured as number of developing embryos). Males preferred to mate with non-parasitized over parasitized females, but showed no differences in association time between females. The nematode did not decrease female body condition, but did decrease female mass, and appeared to decrease female fecundity via reduction in broods (# embryos). Results support that parasites affect male mate choice in mosquitofish; however, the mechanisms used by males to differentiate between parasitized and non-parasitized females remain untested. This study provides the first empirical evidence of parasite affects on male mate choice in livebearing fishes, and suggest a potentially important role for parasite-mediated sexual selection in organisms that use coercive mating as the primary mechanism of obtaining mates.     

丽蝇蛹集金小蜂寄生对寄主蛹可溶性蛋白与芳基蛋白组成与含量的影响

为了探讨蛹期寄生蜂对寄主蛋白代谢的寄生生理效应,利用Bradford蛋白含量测定法、Western免疫印迹法及酶联免疫吸附检测法研究了棕尾别麻蝇Boettcherisca peregrina蛹被丽蝇蛹集金小蜂Nasonia vitripennis寄生后其脂肪体和血淋巴中可溶性蛋白及芳基蛋白组成与含量的变化。结果表明：寄生蛹脂肪体和血淋巴中可溶性蛋白的组成与未寄生相比基本无明显差异; 不论寄生与否寄主蛹脂肪体和血淋巴中芳基蛋白亚基分子量均为80 kDa,该亚基在脂肪体中未出现降解现象,而在血淋巴中仅于寄生后12 h的寄主蛹中呈现2条分子量相近的Western免疫印迹带,说明其降解可能先于未寄生对照。就含量而言,寄生蛹脂肪体中可溶性蛋白含量除寄生后24 h外均显著低于未寄生对照,芳基蛋白含量除寄生后48 h外也均显著低于未寄生对照,其中寄生后12 h的含量仅为未寄生的32.0%。寄生蛹血淋巴中可溶性蛋白含量多低于未寄生蛹,且寄生后2,12,24 h的差异达显著水平;芳基蛋白的含量均有低于未寄生的趋势,其中寄生后12 h的含量为未寄生的17.0%。综合认为,丽蝇蛹集金小蜂的寄生可导致寄主脂肪体和血淋巴中可溶性蛋白及芳基蛋白含量下降。     

Effect of Fruit Load on Partitioning of Dry Matter and Energy in Cantaloupe (Cucumis melo L.)

Cantaloupe (Cucumis melo L.) plants set groups of fruits whichgenerate large variations in the reproductive:vegetative dryweight balance. We studied the influence of fruit number onthe partitioning of dry matter and energy between the vegetativeand reproductive organs and among the seeds and the variousfruit tissues during the development of the first fruits. Over2 years and on two Charentais cantaloupe cultivars, fruit numberwas either limited to one or left unrestricted, which led tothe setting of two to six fruits. Because of the high lipidcontent in seeds, the distribution of assimilates was studiedin terms of energy equivalent as well as dry weight. Measureddry weights were converted into energy equivalents by calculatingthe construction cost of tissues from their elemental composition.Seeds differed from other tissues in showing an increase inconstruction cost, from 1.1 to 1.8 g CH₂O g^-1d. wt between 10and 30 d after pollination. For this reason, during the secondhalf of fruit development on plants with unrestricted fruitload, they made up to 31% of the fruit and 12% of the aerialpart of the whole plant in terms of dry weight, but 39 and 18%in terms of energy (glucose equivalents). The fraction of assimilatesallocated to the fruits showed a saturation-type response tothe number of fruits per plant. It did not increase in cultivarTalma above two fruits per plant, which could be due to a decreasingsink strength with fruit rank, whereas cultivar Galoubet maintaineda more homogeneous fruit size within plants. At a similar fruitload, the reproductive:vegetative dry weight balance differedbetween the 2 years of the experiment, probably because of variationin the fruit sink strength. Copyright 1999 Annals of BotanyCompany Charentais cantaloupe, Cucumis melo L., assimilate distribution, construction cost, development, dry matter partitioning, fruit load, seeds, sink strength.     

EFFECTS OF APEX REMOVAL AND NUTRIENT SUPPLEMENTATION ON BRANCHING AND SEED PRODUCTION IN THLASPI ARVENSE (BRASSICACEAE)

The shoot apex of a plant may be damaged by herbivory, weather conditions, or other factors, leading to growth of some axillary buds into branches. This alteration of branching pattern can affect the location and extent of seed production. I examined the effects of removal of the shoot apex and of mineral nutrient addition on branching and seed production in Thlaspi arvense. Individual plants received no, early, or late apex removal and no, early, or late nutrient addition in a two-way factorial experiment. Apex removal led to greater production of secondary branches. Total seed weight per plant was higher for early- than late-removal plants under all nutrient treatments, but intact controls produced the highest total weight of seeds in two of three nutrient treatments, because their seeds were heavier. Addition of nutrients increased the numbers of secondary branches, fruits, and seeds, and the average and total weight of seeds produced. Apex removal resulted in increased seed production only when it occurred early and when nutrients were added at the same time. Resource availability and plant phenology can be influential in determining the effects of apical damage on seed production, and their effects in combination may differ from their individual effects.     

Susceptibility of Prussian carp infected by metacercariae of Posthodiplostomum cuticola (v. Nordmann, 1832) to fish predation

The susceptibility of prey fish infected by metacercariae of Posthodiplostomum cuticola (Digenea: Diplostomatidae) to the predation of non-host predators under experimental conditions was investigated. Parasitized young-of-the-year Prussian carp Carassius auratus were consumed significantly more often by perch Perca fluviatilis compared to non-parasitized individuals, independent of Prussian carp density. The proportion of parasitized and non-parasitized fish consumed by the predator remained stable at four different prey densities. The probability of predation did not increase with the intensity of parasite infection. The effect of P. cuticola on the host seems to result mostly from pathological changes (poor condition, black spots). However, our results provide evidence of higher probability of parasitized Prussian carp being consumed by fish predators under experimental conditions.     

CO2 effects on apical dominance in Pisum sativum

Alaska pea plants (Pisum sativum L.) were grown at 0.10 vol% and 0.035 vol% CO₂ to determine the effects of high CO₂ concentration upon plant growth and apical dominance. The results showed that a 0.10 vol% CO₂ atmosphere significantly increased the rate of lateral branch, flower bud, flower and fruit development over an environment with 0.035 vol% CO₂. At plant maturity, however, there were no significant differences in the number of branches or fruits produced at the different CO₂ levels. Thus, no evidence was obtained for the loss of apical dominance at the CO₂ concentrations tested. Root dry weight was significantly greater in plants grown at 0.10 vol% CO₂ than in those grown at 0.035 vol% CO₂ and leaf dry weight was significantly lower. However, no significant differences were found in total plant dry weight production at plant maturity.     

Analysis of Branching in Spring-sown White Lupins (Lupinus albusL.): The Significance of the Number of Axillary Buds

Plant density and sowing date were shown to affect branchingin spring-sown white lupin (Lupinus albusL.), but the responsevaried among environments. The patterns of primary and secondarybranching in the cv. Lublanc were studied as a function of boththe number of axillary buds and the plant growth rate. Fieldexperiments that used a wide range of sowing dates and plantdensities to alter plant architecture were conducted over 5years, and these were supplemented with data from additionalglasshouse and growth cabinet experiments. The number of axillary buds on the main stem or primary branches,which determined the potential number of branches, increasedlinearly with the number of nodes. In situations where all axillarybuds did not produce branches, it was found that the numberof primary and secondary branches produced was related to theplant growth rate at the beginning of branch elongation. Knowledgeof the number of axillary buds improved the analysis of theinteraction between cultural practices and environmental conditionson plant architecture. The variability of branching potentialamong genotypes was discussed. Lupinus albus; branches; axillary buds; growth; sowing date; plant density     

Late Transplanting and the Yield of Phaseolus vulgaris L.

The prediction that very high seed yields of dry beans (Phaseolusvulgaris L.) would be produced by the delayed transplantingof large plants has been tested in a factorial experiment withfour dates of transplanting and eight plant populations. Therewere significant differences in yield between transplantingdates and between population densities, and there was a significantdate-density interaction. At low plant densities (up to about30 plants m^–2) the three transplanted treatments yieldedless than the hand-sown controls, and late transplanting yieldedless than early. At the highest density the situation was reversed;all three transplanted treatments out-yielded the controls andlate transplanting tended to out-yield plants transplanted early.The biggest yield was 340 g seed m^–2 from a transplantedcrop grown at 35 plants m^–2. The data on yield fitted a modified rectangular hyperbola ofthe form where y is yield per unit area, p is the number of plants perunit area, t is the number of days between sowing and transplanting,and B_o, n, m, and p are arbitrary parameters. This equationaccounted for 91 per cent of the variation in yield with t andp. It is suggested that late transplanting had adverse effects,due to transplanting ‘shock’ and which were mostmarked at low plant densities; and beneficial effects, ascribableto an effect on plant ‘plasticity’, which were mostmarked at high plant densities. Possible physiological mechanismsof these effects are discussed. Phaseolus vulgaris, yield, density, transplanting     

三种内寄生蜂寄生对小菜蛾幼虫精子发生的影响

内寄生蜂寄生可能会引起寄主的寄生性去势。对小菜蛾Plutella xylostella与菜蛾啮小蜂Oomyzus sokolowskii Kurdumov (膜翅目： 姬小蜂科)、半闭弯尾姬蜂Diadegma semiclausum Hellén (膜翅目： 姬蜂科)、菜蛾盘绒茧蜂Cotesia plutellae (Kurdj.) (膜翅目： 茧蜂科) 3个寄生体系,利用形态学方法和蛋白质技术,研究了寄生对小菜蛾幼虫精子发生的影响。结果表明：菜蛾啮小蜂寄生对寄主的精子发生过程没有影响。半闭弯尾姬蜂寄生造成寄主精母细胞的细胞核畸形,精细胞的染色质超浓缩并趋向核膜,但能形成少量的精子;半闭弯尾姬蜂寄生会导致寄主精巢总蛋白的含量显著下降。菜蛾盘绒茧蜂寄生对小菜蛾幼虫精子发生的抑制程度最强,被寄生寄主的精母细胞出现肿胀,核膜皱缩,胞质中的线粒体发生病变;精细胞的染色体也出现超浓缩并趋向核膜,大量的精子溶解,无正常的精子形成;其精巢总蛋白含量的下降程度比姬蜂寄生的更为明显,且导致分子量为63.4 kD的主蛋白缺失。