Bioefficacy of plant essential oils against pulse beetles Callosobruchus spp. (Coleoptera: Bruchidae) in pigeon pea seeds with particular reference to Clausena pentaphylla (Roxb.) DC.

Thirty essential oils from higher plants of Gorakhpur Division (India) were evaluated at 0.36?μl/ml against two pulse beetles, Callosobruchus chinensis L. and C. maculatus F., causing infestation of pigeon pea seeds during storage. Clausena pentaphylla oil was more effective and exhibited absolute repellency against both the insects followed by Ocimum canum, Salvia plebeia and Zingiber zerumbet oils. Among these four oils, C. pentaphylla oil was most toxic and showed 100% mortality of both the insects at 10-μl dosage and 24-h exposure (LD₅₀?=?2.7?μl for C. chinensis & 2.4?μl for C. maculatus). Physical factors, viz. temperature, storage and autoclaving, did not cause any adverse effect on the toxicity of Clausena oil. During in vivo investigation, the oil protected 1?kg of pigeon pea seeds completely without reducing weight loss and seed damage up to 6?months when stored in gunny bags and glass containers. The oil was standardised by determining its various physicochemical properties. Thus, C. pentaphylla oil can be judiciously exploited as herbal insecticide against pulse beetles of pigeon pea seeds during storage.     

Polyphagy and primary host plants: oviposition preference versus larval performance in the lepidopteran pest Helicoverpa armigera

Oviposition preference and several measures of offspring performance of Helicoverpa armigera (Hübner) were investigated on a subset of its host plants that were selected for their reputed importance in the field in Australia. They included cotton, pigeon pea, sweet corn, mungbean, bean and common sowthistle. Plants were at their flowering stage when presented to gravid female moths. Flowering pigeon pea evoked far more oviposition than did the other plant species and was the most preferred plant for neonate larval feeding. It also supported development of the most robust larvae and pupae, and these produced the most fecund moths. Common sowthistle and cotton were equally suitable to pigeon pea for larval development, but these two species received far fewer H. armigera eggs than did pigeon pea. Mungbean also received relatively few eggs, but it did support intermediate measures of larval growth and survival. Fewest eggs were laid on bean and it was also the least beneficial in terms of larval growth. Among the host plant species tested, only flowering pigeon pea supported a good relationship between oviposition preference of H. armigera and its subsequent offspring performance. Australian H. armigera moths are thus consistent with Indian H. armigera moths in their ovipositional behaviour and larval performance relative to pigeon pea. The results suggest that the host recognition and acceptance behaviour of this species is fixed across its geographical distribution and they support the theory that pigeon pea might be one of the primary host plants of this insect. These insights, together with published results on the sensory responses of the females to volatiles derived from the different host plant species tested here, help to explain why some plant species are primary targets for the ovipositing moths whereas others are only secondary targets of this polyphagous pest, which has a notoriously broad host range. Handling Editor: Joseph Dickens     

Performance of nymphal and adult southern green stink bug on an overwintering host plant and impact of nymph to adult food-switch

Performance of nymphs and adults of the southern green stink bug,Nezara viridula (L.) (Heteroptera: Pentatomidae) feeding on immature fruits of radish,Raphanus raphanistrum L. (Brassicaceae) was poor compared with feeding on immature soybean [Glycine max (L.) Merrill] pods, but a change from radish to soybean from nymph to adult alleviated some of the detrimental effects of this food on adult performance. Over 50% of nymphs died on radish, while only 15% died on soybean. To complete nymph development (stadia 2 through 5), male and female nymphs required 9.5 and 13.3 days longer on radish compared to soybean. Fresh body weight of 1-d-old adult females and males was ≅65% greater for those reared as nymphs on soybean than on radish, with females being significantly heavier than males on both foods. Survivorship and longevity of females, however, was greater for those fed on radish as nymphs and as adults, as compared to those that fed on soybean or radish followed by soybean. Males lived longer when fed exclusively on soybean. In general, reproductive performance and percentage gain in adult body weight was greatest for insects fed on soybean only, and were better for those whose food was switched from nymph to adult, as compared to those insects fed on radish solely.     

Progress of tissue culture and genetic transformation research in pigeon pea [Cajanus cajan (L.) Millsp.]

Pigeon pea [Cajanus cajan (L.) Millsp.] (Family: Fabaceae) is an important legume crop cultivated across 50 countries in Asia, Africa, and the Americas; and ranks fifth in area among pulses after soybean, common bean, peanut, and chickpea. It is consumed as a major source of protein (21%) to the human population in many developing countries. In India, it is the second important food legume contributing to 80% of the global production. Several biotic and abiotic stresses are posing a big threat to its production and productivity. Attempts to address these problems through conventional breeding methods have met with partial success. This paper reviews the chronological progress made in tissue culture through organogenesis and somatic embryogenesis, including the influence of factors such as genotypes, explant sources, and culture media including the supplementation of plant growth regulators. Comprehensive lists of morphogenetic pathways involved in in vitro regeneration through organogenesis and somatic embryogenesis using different explant tissues of diverse pigeon pea genotypes are presented. Similarly, the establishment of protocols for the production of transgenics via particle bombardment and Agrobacterium-mediated transformation using different explant tissues, Agrobacterium strains, Ti plasmids, and plant selectable markers, as well as their interactions on transformation efficiency have been discussed. Future research thrusts on the use of different promoters and stacking of genes for various biotic and abiotic stresses in pigeon pea are suggested.     

Changes in Baboon Feeding Behavior: Maturity-dependent Fruit and Seed Size Selection within a Food Plant Species

Despite considerable inter- and intraindividual variation in fruit and seed size in many plant species, researchers have given little attention to the relevance of the traits for primate fruit choice within a food plant species and its implications for tree regeneration. We studied feeding behavior and selectivity of olive baboons (Papio anubis) in the African locust bean (Parkia biglobosa, Mimosaceae), via direct observations of habituated groups and indirect evidence from leftovers of pods after feeding events. Olive baboons acted as both seed predators and dispersers for Parkia biglobosa. They fed on and destroyed unripe seeds, and swallowed intact ripe seeds when consuming mature fruit pulp. Predation rate was high, and only 10% of the seeds were dispersed. Predation and dispersal of seeds is linked to seed number and size. Digestible unripe seeds accounted for 10% of the unripe fruit mass, while indigestible ripe seeds made up 28% of the mature fruit mass. With these constraints, olive baboons increased food gain per fruit by selecting unripe pods containing a high number of large and heavy seeds. Consequently, only pods with fewer and smaller seeds remained for maturation. Thereafter, baboons fed on mature pods containing the smallest seeds, and exploited pods with more seeds to a greater extent than those with fewer seeds. Thus, fruits with small seeds and an intermediate seed number contributed the most to dispersal by baboons.     

The Development of Desiccation-tolerance and Maximum Seed Quality During Seed Maturation in Six Grain Legumes

‘Physiological maturity’, i.e. the time when seedsreach their maximum dry weight during development, occurredwhen maturation drying on the parent plant in the field hadreduced seed moisture content to approximately 60 per cent infaba bean (Vicia faba L.), lentil (Lens culinaris Medic.), chickpea(Cicer arietinum L.), white lupin (Lupinus albus L.), soya bean(Glycine max [L.] Merr.) and pea (Pisum sativum L.) The onsetof desiccation-tolerance, i.e. the ability of seeds to germinatefollowing harvest and rapid artificial drying, coincided withphysiological maturity, except in pea where it occurred a littleearlier at about 70 per cent moisture content. Maximum seedquality as determined by maximum viability, minimum seedlingabnormalities and maximum seedling size occurred in pea, chickpeaand lupin when seeds were harvested for rapid drying at physiologicalmaturity; but for maximum seed quality in the other speciesmaturation drying had to proceed further - to about 45 per centmoisture content in soya bean and to about 30 per cent moisturecontent in lentil and faba bean seed crops. Much of this variationamongst the six species, however, was due to differences inthe variation in maturity within each seed crop. Results forindividual pods showed that peak maturity, i.e. maximum seedquality following harvest and rapid artificial drying, was achievedin all six species once maturation drying had reduced the moisturecontent of the seeds to 45–50 per cent. In pea, faba beanand soya bean there was a substantial decline in viability andan increase in seedling abnormalities when harvest was delayedbeyond the optimal moisture content for harvest.     

Chromosome Banding Patterns in Some Indian Pulses

By using the Giemsa C-banding technique, chromosome bandingpatterns on the somatic chromosomes of eight important pulsecrops, pea, lentil, guar (cluster bean), chick pea, pigeon pea,mung bean (green gram), urd (black gram) and cowpea have beenstudied. Each species has a characteristic C-banding pattern.The significance of such banding patterns which correlate withthe position of pachytene knobs, in chromosome identification,and in assigning relationships at the cytological level in thepulses of genus Vigna is stressed. Chromosome banding, Giemsa C-banding, pulse crops, Pisum sativum L., garden pea, Lens culinaris Medik, lentil, Cyamopsis tetragonoloba (L.) Taub., guar, Cicer arietinum L., chick pea, gram, Cajanus cajan (L.) Millsp., pigeon pea, Vigna radiata (L.) Wilczek, mung bean, Vigna mungo (L.) Hepper, urd, Vigna unguiculata (L.) Walp, cowpea     

Damage to lima beans by Helicoverpa zea larvae treated as different instars with a nucleopolyhedrovirus

Larvae of the corn earworm,Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), were caged assecond, third, or fourth instars on lima bean,Phaseolus lunatus L., plants in the fieldwith or without treatment of the plants withlethal concentrations of the H. zeanucleopolyhedrovirus. The virus treatmentprevented over 90% of damage to pods and beansif larvae were second or third instars whenplaced in the cages. Damage to pods and beanswas reduced by 73 and 86%, respectively, ifthe larvae were fourth instars when placed onthe plants. When insects survived to the endof the test (which they did only on controlplants), numbers of pods or beans damaged byeach surviving insect was not affected by thestadium in which the larva was when it wasplaced on the plant. This result indicates thatmost damage was done by fourth or laterinstars. If treatments are to effectivelyprevent damage to lima bean, they should thusbe applied before the insects reach the fourthinstar.     

Uptake hydrogenase in Rhizobium and nodule leghemoglobin in cow pea miscellany hosts

Two effective strains of green gram rhizobia S24 (slow growing and Hup⁺) and M11 (fast growing and Hup^-) were tested for leghemoglobin production in nodules and effectivity on six species of cow pea miscellany hosts. Both strains nodulate green gram [Vigna radiata (L.) (Wilczek)], black gram [Vigna mungo (L.) (Hepper)], cow pea [Vigna unguiqulata (L.)], moth bean [Vigna aconitifolia (Jacq.) (Marechel)], Cluster bean [Cyamopsis tetragonoloba (L.) (Taub.)] and pigeon pea [Cajanus cajan (L.)]. In all these hosts, nodules formed by strain M11 contained 1.5 to 2 times more leghemoglobin than the nodules formed by strain S24. Gel electrophoresis of nodule contents of different host species showed a high concentration of a fast-moving ferricoxy leghemoglobin in the nodules of plants inoculated with strain M11 as compared to that of strain S24. Strain M11, however, was relatively less effective than strain S24 on black gram, cow pea and moth bean and was at par with the later on green gram, cluster bean and pigeon pea. Hydrogen recycling ability of the strain S24 was observed in nodules of all the host species. The effective functioning of strain S24 at low levels of leghemoglobin suggests an involvement of recycling hydrogenase in maintaining an appropriate oxidation-reduction potential in nodules.Abbreviations Lb Leghemoglobin - Cvr cultivar     

Seed growth rate in grain legumes I. Effect of photoassimilate availability on seed growth rate

The dry weight of harvested grain legume seeds is strongly related to their growth rate during the period of storage accumulation in the cotyledons, which begins approximately at the end of embryo cell division. Depodding, defoliation, shading or changes in air CO2 concentration were applied during seed filling (i.e. during the decrease in seed water concentration) to field and glasshouse-grown plants, in order to affect the source-sink ratio. The experiments involved three legume species, namely pea (Pisum sativum L.), soybean (Glycine max L. Merr.) and white lupin (Lupinus albus L.). Some treatments affected the number of abortions of less developed seeds from younger pods, but they did not significantly affect the number or the growth rate of filling seeds, demonstrating the priority of carbohydrate partitioning to filling seeds. The maximum growth rate of seeds was achieved regardless of the intra-plant competition level, and the duration of seed growth was shortened if the photosynthetic activity was not sufficient to fulfil the assimilate demand of filling seeds.     

Utilisation of calcium and magnesium and production of acids byRhizobium spp. from some cultivated legumes

A study was made of the utilisation of calcium and magnesium in liquid cultures by 40 strains each ofRhizobium from pea, fenugreek, black gram and lablab bean. The calcium was supplied in the form of calcium carbonate. It was observed that the strains ofRhizobium produced acid. There was considerable variation in the amounts of acid produced and of calcium and magnesium utilised by the different strains of a single species ofRhizobium. Rhizobium from pea, black gram and lablab bean absorbed serveral times more calcium than magnesium. There were strains ofRhizobium from fenugreek which absorbed more calcium than magnesium, while there were others which absorbed more magnesium than calcium.     

Improving nutritional quality and fungal tolerance in soya bean and grass pea by expressing an oxalate decarboxylase

Soya bean (Glycine max) and grass pea (Lathyrus sativus) seeds are important sources of dietary proteins; however, they also contain antinutritional metabolite oxalic acid (OA). Excess dietary intake of OA leads to nephrolithiasis due to the formation of calcium oxalate crystals in kidneys. Besides, OA is also a known precursor of β‐N‐oxalyl‐L ‐α,β‐diaminopropionic acid (β‐ODAP), a neurotoxin found in grass pea. Here, we report the reduction in OA level in soya bean (up to 73%) and grass pea (up to 75%) seeds by constitutive and/or seed‐specific expression of an oxalate‐degrading enzyme, oxalate decarboxylase (FvOXDC) of Flammulina velutipes. In addition, β‐ODAP level of grass pea seeds was also reduced up to 73%. Reduced OA content was interrelated with the associated increase in seeds micronutrients such as calcium, iron and zinc. Moreover, constitutive expression of FvOXDC led to improved tolerance to the fungal pathogen Sclerotinia sclerotiorum that requires OA during host colonization. Importantly, FvOXDC‐expressing soya bean and grass pea plants were similar to the wild type with respect to the morphology and photosynthetic rates, and seed protein pool remained unaltered as revealed by the comparative proteomic analysis. Taken together, these results demonstrated improved seed quality and tolerance to the fungal pathogen in two important legume crops, by the expression of an oxalate‐degrading enzyme.     

Activity of antioxidant enzymes in response to cadmium in Crotalaria juncea

The aromatic amine, -phenethylamine, was identified in various field-grown leguminous plants by analyses with HPLC, GC, GC-MS and ¹H-NMR. High concentration of -phenethylamine was generally detected only in mature root nodules, but not in other plant organs such as root, stem, leaf, pod and grain. Occurrence was specific to the root nodules formed by Bradyrhizobium infection. Ten of eleven legume crops including soybean [Glycine max (L.) Merr.], pigeon pea [Cajanus cajan (L.) Millsp.], adzuki bean (Vigna angularis), mung bean [V. radiata (L.) Wilczek] and cowpea (V. unguiculata) contained this aromatic amine, but groundnut (Arachis hypogaea L.) also nodulated by Bradyrhizobium sp. did not. Root nodules collected from garden pea (Pisum sativum L.), broad bean (Vicia fava L.), kidney bean (Phaseolus vulgaris L.) and various other herbaceous legumes nodulated by Rhizobium sp., Mesorhizobium sp., Sinorhizobium sp. or Azorhizobium caulinodans, and root-nodulated, woody non-legumes, nodulated by Frankia spp., contained little -phenethylamine.The amount of -phenethylamine in Bradyrhizobium-infected nodules varied with the legume species and their cultivars, and most significantly, with nodule age. In field-grown soybean plants, nodule -phenethylamine attained maximum concentration at the flowering stage and far exceeded that of the major polyamines of soybean nodules, putrescine and spermidine.     

Identification of a dispersed MboI repeat family in five higher plant genomes

Digestion of nuclear DNAs of five plants, namelyCucurbita maxima (red gourd),Trichosanthes anguina (snake gourd),Cucumis sativus (cucumber),Cajanus cajan (pigeon pea) andPhaseolus vulgaris (french bean) with the restriction endonucleaseMboI yielded discrete size classes with molecular weights in the range of 0.5 to 5 kbp. TheMboI digestion pattern of Cot 0.1 DNA in french bean is comparable with that of total DNA, indicating that these bands represented highly repeated DNA sequences. Cleavage of the DNAs with varying amounts ofMboI indicated the dispersed nature of the repeat families. Southern hybridization studies using french bean highly repetitive DNA as a probe indicated more homology with repeats of pigeon pea and less homology with red gourd, snake gourd and cucumber repeats.     

Effect of trichome density on soybean pod feeding by adult bean leaf beetles (Coleoptera: Chrysomelidae).

The role of soybean, Glycine max (L.) Merrill, pod trichomes on feeding by adult bean leaf beetles. Cerotoma trifurcata (Forster), was evaluated under laboratory and field conditions during 1997 and 1998. Three Clark isolines and 'Corsoy 79' were used to compare the feeding preference of the beetle on pods with different trichome densities. The three Clark isolines, including densely pubescent, sparsely pubescent, and glabrous, were isogenic except for trichome density. The trichome densities on the pods of Clark densely pubescent, Clark sparsely pubescent, and Corsoy 79 were significantly different. In no-choice tests, under both laboratory and field conditions, the feeding on pods of Clark densely pubescent was significantly lower than that on the other isolines. In the choice test of Corsoy 79 conducted in the laboratory and field, when the trichomes on one of the two pods were shaven off, the feeding on the shaven pods was significantly higher than that of the intact ones. In the choice test among Clark isolines under laboratory condition, the result was significant, with the lowest feeding on the densely pubescent pods. This study demonstrates that densely pubescent soybean has the potential to resist bean leaf beetle feeding on pods.     

Multiple paternity in common bean (Phaseolus vulgaris L., Fabaceae)

We report on two field experiments that were conducted in 1991 and 1992 at the South Coast Extension and Research Center, Irvine, CA, to study the incidence of multiple paternity in the common bean (Phaseolus vulgaris L.). Hypocotyl color and shikimate dehydrogenase (Skdh) isozymes were used as genetic markers. The white-seeded cultivar ‘Ferry Morse 53’ (FM 53) was used as the female parent. This cultivar is homozygous recessive (pp) for hypocotyl color. The pollen source parents were three homozygous dominant (PP) purple-hypocotyled, black-seeded cultivars. Three cultivars, ‘ICA Pijao,’ G4459, and the maternal parent FM 53, are of Mesoamerican origin and homozygous for the fast (F) allele at the Skdh locus. The other cultivar, Black Valentine, is of Andean origin and is homozygous for the slow (S) allele at the Skdh locus. Overall, 6 125 pods were obtained from 57 and 111 plants harvested individually in 1991 and 1992, respectively. All progeny, 28938 seeds, were scored for hypocotyl color at the seedling stage. The purple-hypocotyled seedlings were genotyped for the Skdh locus to identify their pollen parents. Multiple paternity was identified in all the pods with hybrid seeds (i.e., those of intercultivar crosses) at 5.8% and 8.1% in 1991 and 1992, respectively. All multiply sired pods produced both nonhybrid and hybrid seeds. As many as three successful fathers per pod were identified, but the number of markers limited measuring higher levels of multiple paternity. Most multiply sired pods (≈70%) were filled by nonhybrid seeds plus a single hybrid seed. Ovule position effect within multiply sired pods was inferred from the nonrandom distribution of hybrid seeds within a pod. On average, hybrid seeds occurred more frequently in ovules in position 7 (most basal) and in position 1 (most stylar) than in ovules in the middle positions of the pod.     

Infestation of Riptortus pedestris (Fabricius) decreases the nutritional quality and germination potential of soybean seeds

The bean bug, Riptortus pedestris (Fabricius), is one of the major pests of soybean; this pest mainly feeds on soybean pods. Its population is highest when the soybean plants bear mature seeds. We aimed to determine the effect of bean bug infestation on soybean according to changes in nutrient levels and seed germination potential. Newly emerged adult males of R. pedestris (n = 5 per plant) were released into a meshed cage containing soybean plants at the R5 stage. Another meshed cage with soybean plants was treated as control. Healthy seeds harvested from control plants were selected and accounted as undamaged seeds and seeds from bug-released cages were visually categorized into 7 different classes according to the intensity of damage incurred due to bean bug infestation. The seeds were then compared in terms of changes in weight, protein, lipid, and carbohydrate content, and germination potential. Elevated protein levels were observed in seeds that showed a higher intensity of damage. On the other hand, the lipid and carbohydrate contents and germination potential were reduced in seeds showing a higher degree of damage. Germination potential in terms of lipid and carbohydrate loss caused by bug infestation is also discussed.     

Root nodulation studies inAeschynomene aspera

Summary Fifteen isolates of nodule bacteria were isolated from root and stem nodules ofAeschynomene aspera and they were characterized as Rhizobium by well known laboratory tests. All these isolates together with other efficient strains of known rhizobia belonging to different cross-inoculation groups were evaluated for their nodulation abilities onAeschynomene aspera, Cajanus cajan (pigeon pea),Cicer arietinum (chickpea),Pisum sativum (pea),Trifolium repens (clover),Medicago sativa (lucerne),Lens culinaris (lentil),Glycine max (soybean),Vigna sinensis (cowpea),Vigna radiata (mung bean),Vigna mungo (urd bean) andArachis hypogea (peanut). The results demonstrated that Rhizobium fromAeschynomene could form nodules only on its homologous host (Aeschynomene) but not on other legumes tested. Secondly, none of the rhizobia of other cross-inoculation groups could nodulateA. aspera.     

Host recognition by a polyphagous lepidopteran (Helicoverpa armigera): primary host plants, host produced volatiles and neurosensory stimulation

Abstract An important question in the host‐finding behaviour of a polyphagous insect is whether the insect recognizes a suite or template of chemicals that are common to many plants? To answer this question, headspace volatiles of a subset of commonly used host plants (pigeon pea, tobacco, cotton and bean) and nonhost plants (lantana and oleander) of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) are screened by gas chromatography (GC) linked to a mated female H. armigera electroantennograph (EAG). In the present study, pigeon pea is postulated to be a primary host plant of the insect, for comparison of the EAG responses across the test plants. EAG responses for pigeon pea volatiles are also compared between females of different physiological status (virgin and mated females) and the sexes. Eight electrophysiologically active compounds in pigeon pea headspace are identified in relatively high concentrations using GC linked to mass spectrometry (GC‐MS). These comprised three green leaf volatiles [(2E)‐hexenal, (3Z)‐hexenylacetate and (3Z)‐hexenyl‐2‐methylbutyrate] and five monoterpenes (α‐pinene, β‐myrcene, limonene, E‐β‐ocimene and linalool). Other tested host plants have a smaller subset of these electrophysiologically active compounds and even the nonhost plants contain some of these compounds, all at relatively lower concentrations than pigeon pea. The physiological status or sex of the moths has no effect on the responses for these identified compounds. The present study demonstrates how some host plants can be primary targets for moths that are searching for hosts whereas the other host plants are incidental or secondary targets.     

Why do larvae of Utetheisa ornatrix penetrate and feed in pods of Crotalaria species? Larval performance vs. chemical and physical constraints

Larvae of Utetheisa ornatrix (L.)(Lepidoptera: Arctiidae) are found mainly inside unripe pods of several alkaloid‐bearing Crotalaria (Fabaceae) species. Although eggs are laid on the leaves, the larvae are usually found feeding on unripe seeds in the pods. In this work, we investigated the selective pressures that could explain why U. ornatrix larvae feed primarily on unripe pods with seeds and not on leaves. Our results showed that larval survivorship in the laboratory was unaffected by feeding on leaves or unripe seeds, and that larval development up to the pupal stage was better in larvae that fed on unripe seeds, although perforating unripe pods to reach seeds was costly in terms of survivorship. Females were also heavier when fed on unripe seeds, but there was no significant difference in the fecundity of females fed either of the two diets. Feeding on unripe seeds in pods had other benefits for U. ornatrix, including a lower predation rate for larvae that fed inside compared to larvae that fed outside the pods. Similarly, adults derived from larvae that fed on unripe seeds were preyed upon less frequently by the orb‐weaving spider Nephila clavipes than were adults that fed on leaves. The latter benefit may be closely related to the high concentration of pyrrolizidine alkaloids in unripe seeds, which is about five times more than in leaves. These alkaloids are sequestered by the larvae and transferred to adults, which then become chemically protected. However, this chemical defence does not protect the larvae against ants such as Ectatomma quadridens and Camponotus crassus. Pods with unripe seeds that confer physical protection to larvae and pyrrolizidine alkaloids that confer chemical protection to adults limit the use of leaves by U. ornatrix larvae.