In this study, an orthogonal array design with 16 factors at two levels (216) was performed to develop an artificial diet rearing the adults of seven spotted ladybird beetle Coccinella septempunctata. The parameters of weight gain and survival rate of adults, preoviposition period, fecundity and hatching rate of diet-fed adults were monitored. The 16 factors were included: pork liver, infant formula, sucrose, olive oil, yolk, corn oil, yeast powder, cholesterol, casein, casein hydrolysate, vitamin powder, 65% juvenile hormone III, protein powder, vitamin E, honey and pumpkin. Results indicated that pork liver, sucrose, yolk, yeast powder, juvenile hormone, pumpkin and honey were the main ingredients of the artificial diet contributing to weight gain and survival rate of adults, preoviposition period, fecundity and hatching rate. A follow-up fed with a selection of improved formulas confirmed the validity of the optimization as predicted by the orthogonal array analysis, indicating the usefulness of this method for selecting artificial diets for C. septempunctata. The weight gain and fecundity of adults reared on the improved artificial diet were 87.46 and 62.70% of those reared on Aphis craccivora; the survival rate and hatch rate were similar between the diet-fed and aphid-fed, while the preoviposition period was significantly shorter for C. septempunctata fed on the diet than on A. craccivora. The latter formula was superior to any formerly developed formulas and may thus have potential for the improved artificial diet mass rearing of C. septempunctata.

Research on the olive fruit fly Bactrocera oleae (Rossi) – rearing simplification, insect microflora and transgenic strain evaluation – yielded several findings: (1) incorporation of antibiotics in the adult diet is evidently not needed; (2) colonization appears to be easier when wild adults are collected from the field instead of using mature larvae emerging from field-collected infested olives; (3) a combination of standard solid starter with liquid (no cellulose powder) finisher impregnated in synthetic sponge larval diets was more promising compared with all-liquid diets; (4) molecular analysis revealed extensive differences in bacterial species associated with the fly between laboratory flies and strains from different olive varieties, as well as between strains originating from different seasons of the year; (5) when an enhanced green fluorescent protein transgenic strain was compared with the standard long mass-reared strain, it proved significantly inferior according to all quality control tests applied, i.e. egg production, egg hatch, larval-stage duration, pupal recovery, pupal weight, adult emergence and adult survival. The aforementioned findings are discussed in the context of mass rearing and quality requirements for more successful implementation of the sterile insect technique against this pest.

Mass-rearing protocols must be developed, in particular, a cost-effective larval diet, to implement the sterile insect technique against Anastrepha fraterculus (Wiedemann). The key elements of this diet are the optimal nutrients and their concentrations, diet supports or bulking agents, and the pH of the diet. To improve the currently used formulation and develop a more cost-effective diet, in the present study, we evaluated various supports, sugar contents, nutrient proportions and pH levels. Egg-to-pupa recovery was found to increase when agar was replaced with sponge cloth in the diet. Although low, the recovery values obtained when using the sugarcane bagasse-based diet were similar to those obtained when using the agar-based diet, but the percentage of adult emergence was lower. Larval viability was found to increase when the amount of sugar in the diet was doubled. Yet, it is still necessary to evaluate this diet on a larger scale and determine the feasibility of reusing the sponge cloth to reduce the costs of larval diets.

Several aspects of the biology of Xylotrechus arvicola (Olivier), an emerging grape pest, were studied under laboratory conditions. Four diets were tested to rear this species in the laboratory. Among them, only one made rearing from larva to adult possible. The highest mortality, in all cases, was recorded during the first days of larval development. Larvae were kept 45 days at 8°C to break diapause in order to reduce the normal field larval developmental time. The species' developmental time was similar between sexes, while pupal developmental time and weight were significantly greater for females than for males. As part of a complementary study, life table parameters of females obtained from the larvae reared on the artificial diet were compared to those of females emerged from field-infested grape root wood. Both laid the majority of eggs in the first two weeks after emergence, and they had a similar pre-laying period. Nevertheless, the females from the diet-reared larvae lived significantly longer, laid eggs over a longer period of time and showed higher fertility than those emerging from infested grape root, suggesting that diet fulfils larval nutritional needs. The species’ laboratory-reared population exhibited a low intrinsic growth rate value (rm=0.01) as a result of its long egg-to-adult developmental time and its high larval mortality.

Host-plant resistance is one of the major components of integrated pest management programmes against the noctuid pod borer Helicoverpa armigera (Hübner) in chickpea. Survival and development of H. armigera on nine chickpea genotypes were compared using two food substrates, namely fresh leaves and pods, and artificial diets containing lyophilized leaf or pod powder of the same genotypes. Among the genotypes used, six showed different levels of resistance to H. armigera, while three were used as susceptible checks. Using leaves and pods, five of the resistant genotypes yielded lower larval weights compared to one of the susceptible checks used. Significant differences between four of the resistant and two of the susceptible genotypes were also observed when using artificial diets containing leaf or pod powder, but the rankings were different from that on the fresh leaves and pods. On both substrates, four resistant genotypes resulted in lower larval survival, pupation, adult emergence and fecundity when compared to one of the susceptible checks. A similar trend was also observed for larval survival and development when using F1 hybrids based on four of the resistant genotypes. Survival and development of H. armigera on the two food substrates, fresh leaves and pods and artificial diets with lyophilized leaf or pod powder, were highly correlated, suggesting that incorporation of lyophilized leaves or pods into the artificial diet can be used to assess antibiosis to H. armigera in chickpea.

Euproctis latifascia Walker is an important pest attacking old leaves of tea bushes and mother leaves of nursery cuttings in Darjeeling foothills, Terai and Northeast India. Laboratory experiments were designed to assess the effect of an artificial diet and a natural diet, i.e. tea leaves, Camellia sinensis, on life history traits like development time, survival and fecundity of E. latifascia. In addition, the maintenance cost as well as the nutritional and production indices were estimated for each substrate (diet) using the gravimetric (dry mass) methods. On the natural (tea leaves) and artificial diets, the total development periods were 78.4 and 68.6 days, fecundity 248.8 and 230.3 eggs/female; in the final caterpillar stage (VI), the relative consumption rates were 0.8 and 0.6, relative growth rates 0.05 and 0.07, maintenance costs 5.1 and 2.9 and production index 0.1 and 0.2, respectively. The fifth instar larvae also showed similar differences in their nutritional indices. Based on these parameters it appears that the artificial diet is more suitable for laboratory rearing of E. latifascia than the natural tea-leaf diet.

An artificial diet was developed for mass rearing of the spotted bollworm Earias vittella (Fabricius) in environmentally controlled conditions (27±1°C, 65±5% R. H. and 16:8 h scoto/photophase). The ingredients for 1 l of diet consisted of soybean (Glycine max) flour (60.0 g), chickpea (Cicer arietinum var. kabuli) flour (58.0 g), wheatgerm (16.0 g), dried yeast powder (16.0 g), casein (8.0 g), l-ascorbic acid (2.4 g), cholesterol (0.4 g), methyl-p-hydroxybenzoate (0.4 g), sorbic acid (2.4 g), streptomycin sulphate (0.4 g), agar–agar (16.0 g) and distilled water (820 ml). The artificial diet developed showed a higher development index (3.58) and a higher survival rate (83.4%) compared to the most preferred natural food (okra pods), for which these parameters were 3.09 and 65.0%, respectively. All the ingredients of the diet are easily available and inexpensive. The cost of 1 l of the diet, on which 400 larvae can be reared, is approximately US$ 2.00.

An artificial diet for mass rearing of the tobacco caterpillar Spodoptera litura (Fabricius) from the neonate to adult stage was developed at 27±1°C, 65±5% RH and 16:8 h scoto/photo-phase regime. The diet ingredients consisted of wheat germ (26.0 g), kidney bean flour (51.3 g), chickpea flour (56.0 g), yeast powder (31.6 g), casein (15.2 g), l-ascorbic acid (3.2 g), cholesterol (0.5 g), two multivitamin multimineral capsules, one vitamin E capsule, ABDEC drops (2 ml), castor oil (1 ml), methyl-p-hydroxybenzoate (1.8 g), sorbic acid (1.3 g), streptomycin sulphate (0.25 g), formaldehyde solution (2 ml), agar–agar (16.4 g) and 820 ml distilled water. The new artificial diet successfully supported the growth and development for more than ten generations with enhanced reproductive potential. The mean biological parameters based on rearing of ten continuous generations showed higher pupation (89.2%), emergence (97.2%), survival (86.6%) and fecundity (2486.2 eggs) as compared to the most preferred natural food, castor leaf whose respective recorded values are 80, 75, 60% and 480 eggs. The cost of 1 l of the diet was approximately US$ 2.00 only, on which 200 neonate larvae can be reared. The artificial diet developed is suitable for mass rearing S. litura successfully throughout the year for laboratory and field experimentation as well as for commercial production of nuclear polyhedrosis viruses (Sl NPV).

Cerconota anonella is the most important pest of the Annonaceae in the Neotropical region for larval damage, which can result in 60 to 100% losses in fruit production. However information on the pest's biology is scarce. This research compared different artificial diets for rearing C. anonella under laboratory conditions (25.0 ± 1.0 °C; 60 ± 5.0% RH and 14 h photophase). Five diets were compared: A (bean, soybean meal, wheatgerm, casein and yeast), B (maize flour, wheatgerm and yeast), C (wheatgerm and casein), D (wheatgerm and soybean) and E (wheatgerm and soybean). In diet E, the amount of wheatgerm was higher than that in dietD. The results indicated that diet E was the most suitable one for the development of C. anonella.

Growth, development and fecundity of Maruca vitrata Fabricius (Lepidoptera: Crambidae) were studied on artificial diet and flowers of two accessions each of three wild Vigna species, namely V. vexillata (TVnu 594 and TVnu 72), V. oblongifolia (TVnu 957 and TVnu 42) and V. unguiculata ssp. dekindtiana (TVnu 979 and TVnu 863) and six accessions of cowpea, V. unguiculata ssp. unguiculata (Moussa Local, VICAM-1, TVu 13731, IT84S-2246, IT89KD-457 and IT91K-180). The percentage survival of the larvae, larval weights as well as growth and development indices were significantly higher on the artificial diet, flowers of cowpea cultivars and those of V. unguiculata ssp. dekindtiana compared to those of V. vexillata and V. oblongifolia. The fecundity of females from larvae reared on artificial diet and flowers of cowpea was also significantly higher than that of females from the wild Vigna genotypes. All variables were included in principal component analysis. Two components accounted for 81.79%. On the basis of this analysis, the diets appeared to fall into four categories based on their suitability for supporting development of M. vitrata: unsuitable (TVnu 42 and TVnu 957), fairly suitable (TVnu 72, TVnu 594, TVnu 979, Moussa Local and TVnu 863), suitable (IT89KD-457, IT91K-180, VICAM-1, TVu 13731 and IT84S-2246), and very suitable (artificial diet). The importance of these findings in the development of host plant resistance of cowpea to M. vitrata is discussed.

An artificial diet for rearing the spotted bollworm, Earias vittella (Fabricius) was developed under laboratory conditions (temperature 27 ± 1°C, RH 60 ± 5% and 16:8 h scoto /photophase regime). The diet ingredients consisted of wheatgerm (5 g), seeds of cotton (Gossypium hirsutum L. var. Pusa 8–6) (50 g) and chickpea (Cicer arietinitm L. var. Kabuli)(35 g) as base materials along with agar-agar (15 g), dried yeast powder (8.0 g), methyl-p-hydroxybenzoate (1.0 g), l-ascorbic acid (1.2 g), sorbic acid (1.0 g), cholesterol (0.2 g), streptomycin sulphate (0.2 g), and multivitamin multimineral and vitamin E capsules (one each). After rearing neonates on okra for 3–4 days, the diet supported the growth and development of E. vittella successfully for eight generations. Larval development on this diet was completed in 11.9 ± 0.66 days against 11.64 days on the pest's preferred natural host, okra (Abelmoschus esculentus) Moench. The growth and developmental indices on the artificial diet for the eight generations are reported.

In the framework of echinoid cultivation, whose objective is to succeed in continuously producing large amounts of edible sea urchins (Paracentrotus lividus) under controlled conditions (aquaculture), gonadal growth is to be optimized. Among the various parameters influencing the production of roe, the quantity of food distributed was tested for optimization. After a 1-month fast, echinoids were fed artificial food pellets (enriched in soybean and fish proteins) for different periods of time over 48 h, the food thus being available ad libitum for 8, 16, 24, 32, 40, and 48 h; the cycles were repeated for a month. The results show that the quantity of food intake and the gonad index peak after about 35 h of food availability. This suggests food should be distributed discontinuously for optimal gonad production and minimal waste.

The composition and preparation of an artificial diet for the coffee berry borer, Hypothenemus hampei is described. Ten generations were obtained without any significant change in fecundity. Development at 25°C on this diet was similar to previously reported work using coffee berries. One female reared on this diet lived for 380 days. This diet will permit investigations into the genetics of insecticide resistance, potential biopesticides and other research, requiring a convenient laboratory rearing system.

The lowest weight at which a final instar larva of the leafroller, Cnephasia jactalana (Walker) (Lepidoptera: Tortricidae) can initiate pupation, the larval critical weight, was unaffected by diet quality. Use of a non-nutritive artificial diet showed that the larval-pupal metamorphosis was possibly triggered by stretch receptors, and was not related to nutrition per se. However, a final-instar larva was not able to moult until it had ingested and assimilated the quantity of food required to attain the larval critical weight. The period between attaining the larval critical weight and the larval maximum weight is the latent feeding period which was found to be longer on higher-quality diets. The decrease from larval maximum weight to pupal weight depended on diet quality: optimum-quality diets gave the smallest decreases. The decrease from pupal to adult weight was not affected by diet. Reproductive performance was strongly affected by the quality of the diet during the latent feeding period.

Artificial diets were formulated and evaluated for their suitability to rear the spotted bollworm, Earias vittella, a major pest of cotton and okra. The most satisfactory diet consisted of maize semolina 11%, wheat bran 4.6%, soybean powder 2.4%, yeast 1.4%, salt mixture 0.9%, ascorbic acid 0.3 %, cellulose 0.9 %, agar 1.8%, water 76.7% and preservatives. The insect was reared on this diet for 10 generations without any adverse effect on its development and reproductive potential.

Mussidia nigrivenella Ragonot is the main cob borer of maize in Ivory Coast. An accurate description of male and female genitalia is given. Rearing in the laboratory has permitted determination of the number and duration of the pre-imaginal instars, fecundity of adults and fertility of eggs as also the sex-ratio. An artificial diet has been elaborated which provides conditions of similar development to those observed in the field: The insect has 5 to 6 larval instars and the total duration of development from the egg-laying to the adult emergence is 46 days for the male and 49 days for the female.

Several species of Chilo are serious pests of cereal crops. The important species attacking cereals are Chilo agamemnon, C. orichalcociliellus and C. partellus on maize and sorghum; C. auricilius and C. zacconius on sugar-cane, and rice; C. suppressalis on rice; and C. sacchariphagus indicus on sugar-cane. Insects are reared in the laboratory on natural and artificial diets for various purposes, namely for insecticide testing, hormone and pheromone manipulation, biological control, host-plant resistance, etc. Rearing of an insect in the laboratory requires rearing facilities, colony establishment, research and development of rearing techniques, resources, and maintenance of insect quality. All these aspects for rearing major Chilo spp. have been discussed. However, detailed information is available only for C. partellus and C. suppressalis. Techniques used for resistance screening and damage evaluation against spotted stem borer, C. partellus using naturally occurring population and artificial infestation are described.

Common carp larvae were fed artificial diets over 28 days at about 24 °C. Diets were based on yeast and either beef liver or casein. Survival rates of larvae were 76-92% with liver diets and 87-96% with casein diets. Larval growth was superior with liver diets (mean final weights 720-880 mg) than with casein diets (130-340 mg). Within-tank coefficient of variation of body weight increased with mean weight according to a generalized S-shaped curve. The skewness coefficient tended to increase with the mean weight, with higher values in the casein-fed group than in the liver-fed group. It is concluded that liver is not strictly indispensable for carp larvae diets and may be replaced by less complex components.

A low cost artificial diet was formulated from materials which are locally available in Africa. The diet utilized cowpea, sorghum and corn instead of pinto bean and wheat which are widely used in the USA. The new diet was as satisfactory as the pinto bean diet for all the biological criteria tested. On a pinto bean diet, pupation and eclosion required 14.3 ± 1 and 26.3 ± 1 days, respectively. On the cowpea diet, 14.6 ± 1 and 26.9 ± 1 days were required, respectively. Ninety-eight per cent of adults eclosing on each diet were viable. Females eclosing on the cowpea diet laid 739 ± 53 eggs of which 59 ± 2% hatched. On the pinto bean diet, 774 ± 62 eggs were laid per female with 61 ± 2% hatching. Pupal weights were 526 ± 22 and 537 ± 28 mg when larvae were reared on the pinto bean and cowpea diets, respectively. Food consumption and utilization by larvae reared on the new diet were comparable with those of larvae reared on the popular pinto bean diet.

Eleven artificial diets with principal base-ingredients as pulses and beans, viz. winged bean, Psophocarpus tetragonolobus; green gram, Vigna radiata (L.) Wilczek; dew gram, Vigna aconitifolia (Jacq.) Marichat; broad bean, Vicia fabia (L.); soybean, Glycine max Merr.; and cluster bean, Cyamopsis tetragonoloba Taub., were formulated either alone or in combination, for the mass rearing of Chilo partellus (Swinhoe). On the basis of important biological parameters having direct bearing on the selection of media for rearing, seven diets were unsuitable. These diets were compounded with either winged bean, soybean grains (dry and water soaked), or broad bean or with different quantities of cluster bean blended with green gram and dew gram as principal base-ingredients. The superiority of the remaining four diets based on (i) kidney bean, (ii) kidney bean + sorghum leaf powder, (iii) green gram + dew gram, and (iv) green gram + dew gram + sorghum leaf powder, was established. The modified green gram + dew gram + sorghum leaf powder-based diet has an added advantage over its original version due to low cost of production of moths and eggs in both the generations. This highlights the formulation of a new modified diet which can be utilized not only as an alternative to the original green gram + dew gram based diet but also can replace it to overcome the phenomenon of inbreeding depression due to continued rearing in the same diet.