Ostrinia nubilalis Hübner (Or.: Lepidoptera, Fam. :

Transcription

1 Comm. Appl. Biol. Sci, Ghent University, 77/4 567 Comparative Studies of Semi-artificial diets on the Biology and the Bionomics of the European corn borer, Ostrinia nubilalis Hübner (Or.: Lepidoptera, Fam. : Pyralidae) By SUMMARY A.S.A. SAAD, A.K.K. MOURAD, M.A. MASOUD and M.A.S. GHORAB Plant protection Department, Faculty of Agriculture Saba Basha, Alexandria University, Egypt. Comparative studies of two semi-artificial diets (S.A.1 & S.A.2) as well as a natural corn diet were studied on the biology and bionomics of the European corn borer, Ostrinia nubilalis under laboratory conditions. The insect was successfully mass reared for ten successive generations at the conditions of 27± 2 C, 60-80% R.H. in addition of photoperiod of 6:18 (L: D) for larvae and 12:12 (L: D) for the other stages respectively. Along ten successive generations, there were no significant differences between the larval periods for both artificial diets. The S.A.1 induced the shortest larval period (22.5 days) compared to the artificial diet S.A.2 (24 days) and the natural diet (25 days). Meanwhile, the rearing larvae on the natural diet revealed means of pre-pupal and pupal periods of 2 and 8 days which decreased to 2 and 6.5 days in both artificial diets (S.A.1 and S.A.2), respectively. However, the pupal weight and length were insignificantly increased in S.A.1 (121.7gm and 1.7 cm) than that in the natural diet (115.5 gm and 1.8 cm) and were in the artificial diet S.A.2 ( gm and 1.7 cm), respectively. Moth longevity (pre-oviposition, oviposition and post-oviposition periods), was affected to a certain extent by the larval diets. The maximal moth longevity was recorded (15 days) for larva reared on the natural diets. On the other hand, the shortest period was observed (10.5 days) for the moth longevity in S.A.1. The artificial diet S.A.2 showed the moth longevity (13 days). The longest oviposition period was recorded (10 days) in the natural diet, while it was only (6.5 days) in the artificial diet S.A.1 compared with (8 days) in the artificial diet S.A.2. The number of the deposited eggs/female throughout the 10 successive generations was (400) in the natural diet, while the artificial diet S.A.1 revealed the least number (304.4 )versus (358.2) in the artificial diet S.A.2. On the other hand, the number of hatched eggs/female were (320) in the natural diet, versus (310.9 and 256.5) in the artificial diet S.A.2and S.A.1 consequently. The highest mean of hatchability percent was 86.93% resulted in the artificial diet S.A.2 compared to % in the artificial diet S.A.1 and 80 % in the natural diet. It was observed that the shortest total generation

2 Comm. Appl. Biol. Sci, Ghent University, 77/4 568 period found (41.5) days in the artificial diet S.A.1 while it was (50 and 45.5)days in the natural diet and the artificial diet S.A.2, consequently. The results declared that the artificial diet S.A.1 is a suitable artificial diet as it is considered mass rearing of the European corn borer, Ostrinia nubilalis Hub. INTRODUCTION Maize is one of the most important cereal crops in several developing countries. It grows over wider geographical range and different ecological conditions than any other cereal crop, the maize considered to be the second most important cereal crops after wheat on global basis (Cimmyt& Earo,1999). In Egypt, the Egyptian farmers use it for animal feeding, as well as human nutrition. Such importance has kept the maize acreage without reduction in comparison with to the other cultivated crops. The annual cultivated area with maize covers about two million feddans. (Mesbah et al., 2002).The national average yield of maize, which is about 1.7 ton ha -1, is below the world average of 3.7 ton ha -1, but slightly better than the average in Africa (Benti and Ransom, 1993; Masoud et al, 2010). Lepidopteron stem borers are one of the major constraints of maize production worldwide as well as in Egypt. (Warui and Kuria, 1983; Seshu and Walker, 1990 and El-Metwally et al, 1997). Corn plants are usually attacked by several common injurious insect-pests, i.e, The Pink stem borer, Sesamia certica led, The Purple-lined borer, Chilo agamemnon (Bles.) and The European corn borer, Ostrinia nubilalis (Hub.), which are regarded among the major factors affecting the productivity of growing maize plants, and causing great damage and yield losses. (Salama and Tolba, 1971; El-Metwally et al., 1997; Masoud,2005and Masoud et al., 2010). The European corn borer (ECB) Ostrinia nubilalis (Lepidoptera: Pyralidae) is a major economic pest of corn (Zea Mays), and is considered one of the most damaging borers of maize in Egypt. The larvae of ECB cause direct losses by boring into plant stems or ears in addition to indirect losses by facilitating the infection by micro-organisms. ECB larvae act as vectors of Fusarium, causing kernel rot (Sobek and Munkvold, 1999). In Germany, the yield losses due to ECB in testcross hybrids amounted to 40% (Kreps et al, 1998). In Egypt, Semeada (1998) found that 13-18% reduction in yield of maize was due to Ostrinia nubilalis Bohn et al, 1999, found that ECB infestation reduced average maize grain yield of the hybrids by 0.28% for each 1% of damaged plants and by 6.05% for each European corn borer larvae per plant. Also, Szoke et al. (2002) found that losses caused by this pest ranged from kg/ha. The success of insect rearing and quality control research plus the widespread implementation of rearing programs have transformed Entomology into a highly scientific and technical field. It has provided expansion of Entomology in ways that would not have been possible without a dependable supply of laboratory-reared insects. Much of this success, directly

3 Comm. Appl. Biol. Sci, Ghent University, 77/4 569 or indirectly, is due to contributions fostered by the insect rearing researcher. (Anderson, and Leppla, 1992). The insect rearing is a dynamic field, where new techniques are constantly being invented and the existing techniques are improved from time to time, with changes in demand and technological evolution. (Barbulescu,1996; 1998; 1999;and 2001). In the light of previous mentioned statements, corn borer Ostrinia nubilalis are reared with the aim of having enough insect population for biological and toxicological studies. The success of any insect pest control program relies on continuous supply of high-quality insects in adequate numbers, at specified times and at stages of development. MATERIALS AND METHODS The rearing artificial diet was applied for a long generation time rear Ostrinia nubilalis (Hub.) in Faculty of Agriculture, Saba Basha, Plant Protection Department Laboratory using corn leaf powder, brewer s yeast, soybean, meal corn, wheat germ, agar, corn flour and water, Furthermore, five semi artificial diets were also prepared and initiated on the place. The five semi-artificial diets were investigated to select the most appropriate for all corn borer insects. Two semi-artificial diets (S.A.1 and S.A.2) seemed to be promising for rearing the European corn borer, Ostrinia nubilalis Hub. and effectively in biological and toxicological research studies. Preparation of the semi artificial diets: Both semi-artificial diets were prepared in the lab. The 1 st semi-artificial diet S.A.1 composed of 3 component fractions (A, B and C) while the second one S.A.2 composed of 4 (A, B, C and D). Noticeably, fraction A of the contained maize leaf powder (stalk leaves of plants six weeks old, dried in air oven at 90 C for 10 hrs till brittle and ground using mill) and bean (phaseolus vulgaris) powder, While S.A.2 contained corn meal (ear leaves of plants 11:12 weeks old dried in air oven at 90 C for 10 hrs till brittle and ground using mill), Green bean in fraction A and corn flour in fraction D as well as corn ear-leaves meal in fraction D. The Components (Tables,1&2) and the preparation procedures of both semi-artificial diets were as follows: S.A.1 semi-artificial diet (Table 1): 1. Mix all the ingredients of Group A. 2. Put B-1 into B-2, Stir, and allow the maize leaf powder to absorb water fully for several minutes. 3. Keep boiling, and stir for 5 min. to increase the viscosity of the agar solution. Add C-1 directly into the boiling agar solution with constant stirring. A larger container may be needed to avoid overflowing. Stop heating and add the mix of A. 4. While the complete diet mixture is still liquid, pour it into rearing containers with a ladle and cool. After the diet solidifies, cut it with long-armed forceps to put it in the glass tube of rearing. 5. After the diet is dispensed, keep the containers open for 2 hours to allow the escape of the excessive moisture, after that they are covered with a clean white cloth or paper towel and then left to gel and condition overnight at room temperature on a bench in the laboratory.

4 Comm. Appl. Biol. Sci, Ghent University, 77/4 570 Table (1): Ingredients of the semi-artificial diet S.A.1 Quantity per (g) or (ml) per 3 liter diet Ingredient Fraction A 1. Maize leaf powder * 2. Bean(phaseolus vulgaris)powder # 3. Brewers yeast powder 4. Ascorbic acid 5. Sorbic acid 6. Methyl-p-hydeoxybenzoate (Dissolved in 20 ml Ethanol, absolute ) 6. Vitamin E capsules 7. Sucrose 8. Distilled water Fraction B 1. Agar powder 2. Distilled water Fraction C 1. Formaldehyde (40%) O. nubilalis ( in 6.66 ml Ethanol * Six weeks old leaves, dried in air oven at 90 C for 10 hrs till brittle and ground using mill. # Seeds washed with tap water, dried in the oven at 60 C for 24 hrs and ground to fine powder. S.A.2 semi-artificial diet (Table 2): 1. Mix the three (A1, A2, A3) ingredients of Group A. 1. Mix B-1 and B-3 with B-2 and then add A-4 after dissolving, pour them into Group A. 2. Put C-1 into D-2, Stir, and allow the corn meal to absorb water fully for several minutes then add C-3 by stirring well. 3. Put D-1 into B-3 and heat the mixture until ingredients are fully dissolved. Add group C, Keep boiling, and stir for 5 min. to increase the viscosity of the agar solution. Add D-2, D-3 directly into the boiling agar solution with constant stirring. A larger container may be needed to avoid overflowing. Stop heating and add D While the complete diet mixture is still liquid, pour it into rearing containers with a ladle and keep it to cool. After the diet solidifies, cut it with long-armed forceps to put it into rearing glass tube.

5 Comm. Appl. Biol. Sci, Ghent University, 77/4 571 The diet is dispensed into heat-sterilized (100 C for 30 mints), wide-mouthed glass jars (19.0 X 7.5 cm), each jar containing approximately 100 g diet. The diet is allowed to gel and to condition overnight at room temperature while covered with a clean white cloth or paper towel. (Singh and Moore, 1985; Songa et al., 2001 and Masoud et al., 2010). Table( 2): Ingredients of the semi-artificial diet S.A.2 Quantity per 100 g diet (ml) Ingredient Fraction A 1. Corn meal 2. Water 3. Erythromycin 4. Green bean Fraction B 1. Ascorbic acid 2. Sucrose 3. Water Fraction C 1.Methyl-p-hydeoxybenzoate (Dissolved in 20 ml Ethanol, absolute) 2.Vitamin E capsules 3. Sorbic acid Fraction D 1. Agar 2. Corn meal 3. Corn Flour 4. Brewers yeast powder 5. Formaldehyde (40%) Ostrinia nubilalis 12.70g 40.41ml g 0.25g 0.10g 46.47ml 0.10g 0.02g 0.09g 1.25g 10.20g 2.54g 2.35g 0.19ml * Six-week- old leaves, dried in air oven at 60 C for 10 hrs till brittle and ground using mill. Seeds washed with tap water, dried in the oven at 60 C for 24 hrs and ground to fine powder. Insect mass rearing management: In the beginning the deposited eggs were collected for the previous reared insect in natural diet for 4 generations were collected. Upon hatching larvae were introduced singly into heatsterilized glass test tube containing the diet. (Barbulescu, A., 1996; 1998; 1999 and 2001). The test tube covered with a cotton wool, feed undisturbed until pupation and eventual adult emergence. The test tubes kept at the conditions of 27± 2Ċ, over 78% relative humidity (RH). In addition to photoperiod of 8:16 (L: D) for larvae and 12:12 (L: D) for the other stages, respectively.

6 Comm. Appl. Biol. Sci, Ghent University, 77/4 572 Adults were removed daily from the rearing jars, using a battery-operated hand aspirator or glass vials (9.5 x 4.5 cm), and transferred to a rectangular oviposition cage (40 x 30 x 40), made of wire frames covered with wire mesh. The inside of the cage is lined with butter paper, pleated vertically to form an internal lining of the cage for the moths to deposit their eggs on and for rest. The top of the cage is fitted with a mosquito-netting sleeve to facilitate the introduction of the butter-paper, adult diet (tap water with 10% sugar into cotton wool and placed into a Petri dish) and moths into the cage. A maximum of 100 adult pairs are introduced into the cage. (Anderson, and Leppla, 1992; Odindo and Onyango, 1998 and Masoud et al., 2010). Waxed paper (called butter-paper) were used for eggs oviposition. The pieces of waxed paper were removed daily from the oviposition cage. The egg batches were cut using either pair of scissors or scalpel blade, and placed in a lunch-box on moist filter-paper and covered with a well-ventilated top. Incubation takes place at ambient laboratory conditions at 27 ± 2 C and 78% relative humidity (Odindo and Onyango, 1998). Eggs were each dropped into a jar containing the diet to continue the mass rearing on the semi-artificial diets. Biological study: The deposited eggs were collected for the previous reared insect in natural diets (maize stalk pieces and leaves) for 4 generations to build up genetic homogenate strain. Three replicates of st instar larvae were employed for each of natural or semi-artificial diets. The insects were reared for 10 generations on the natural diet. The mean of the biological parameters was used as a reference generation to evaluate the efficacy of both semi-artificial diets (S.A.1 and S.A.2). The evaluation was continued for 10 successive generations. Statistical analysis: Data were subjected to the analysis of variance test (ANOVA) and Randomized Complete Block Design (F. test). The least significant differences (LSD) at the 5% level were determined according to computer program Costat and Duncan's Multiple Range test (DMRT) mod ified by (Steel and Torrie,1980 and Costat Software, 1990). RESULTS AND DISCUSSIONS Effect of semi artificial diets on the biology and the bionomics rearing of the European corn borer, Ostrinia nubilalis Hub. : Larval stage: The data on tables (1 and 2) clarify the effect of the semi artificial diets on the larval stage periods of the European corn borer. The larvae fed on S.A.1 showed that there were no significant differences between the larval longevity periods along ten successive generations. The only significant differences were detected in the 4 th and 5 th generations in the artificial diet

7 Comm. Appl. Biol. Sci, Ghent University, 77/4 573 S.A.2 that showed 23 days for both. Moreover, the mean of the larval period throughout 10 generations was significantly decreased to (22.5 days) in S.A.1 compared to the natural diet (25 days). While, he artificial diet S.A.2 recorded 24 days. Table (1). The effect of (S.A 1) on larval stage period of the European corn borer, Ostrinia nubilalis Hub. Generation Larval stage period (days), at 27 ± 2 C and photoperiod: 6:18 (L:D) 1 st instar 2 nd instar 3 rd instar 4 th instar 5 th instar Total 1 St b 2 nd b 3 rd b 4 th b 5 th b 6 th b 7 th b 8 th b 9 th b 10 th b Mean b Reference b generation * In a column the means are followed by the same letter are not significantly different at the 5% level by DMRT Table (2). The effect of (S.A.2) on larval stage period of the European corn borer, Ostrinia nubilalis Hub. Larval stage period (days), at 27 ± 2 C and photoperiod: 6:18 (L:D) Generation 1 st instar 2 nd instar 3 rd instar 4 th instar 5 th instar Total 1 St b 2 nd b 3 rd b 4 th b 5 th b 6 th b 7 th b 8 th b 9 th b 10 th b Mean b Reference b generation * In a column the means are followed by the same letter are not significantly different at the 5% level by DMRT

8 Comm. Appl. Biol. Sci, Ghent University, 77/4 574 Pupa stage: In respect to the pre-pupal and pupae periods, there was no significant difference between the artificial diets S.A.1 or S.A.2 and with the natural diet throughout the ten generations. Meanwhile, rearing larvae on natural diet revealed means of pre-pupal and pupal periods of 2 and 8 days which decreased to 2 and 6.5 days in the artificial diet (S.A.1 and S.A.D2), respectively (Table, 3). Moreover, the artificial diet (S.A.1) insignificantly increased the calculated means of pupal weight 121.7gm, while S.A.2 insignificantly decreased it to gm compared with the natural diet gm. However, the pupal length was (1.7 cm) insignificantly decreased in (S.A.1 and S.A.2 ), respectively. While, it was (1.8 cm) in the natural diet. Table (3). The effect of S.A.1 and S.A.2 on the pupal duration and biological bionomics of the European corn borer, Ostrinia nubilais Hub. Biological duration and bionomics of pupa stage Generation S.A.1 S.A.2 Prepupae (days) Pupae period (days) Weight of pupae (mg) Length of pupae (cm) Prepupae (days) Pupae period (days) Weight of pupae (mg) Length of pupae (cm) 1 St 1.5 a 6.0 b b 1.6 b 2 a 7 b c 1.2 c 2 nd 2.0 a 6.0 b c 2 a 7 b c 1.5 c 3 rd 2.0 a 6.0 b d 1.5 b 2 a 6 c c 1.6 c 4 th 1.5 a 7.0 b bc 1.7 b 2 a 6 c 98.8 d 1.4 c 5 th 2.0 a 6 b a 1.7 b 3 a 6 c 95.9 e 1.5 c 6 th 2.0 a 6.0 b ab 2.1 a b 3 a 6 c b 2.2 a 7 th 2.0 a 6.5 b bc 1.9 b 2 a 7 ab bc 1.7 ab 8 th 1.5 a 8.0 a 99.5 d 2.2 a 2 a 7 ab b 1.9 c 9 th 1.5 a 8.0 a c 1.2 b 2 a 6 c c 2.3 a 10 th 2.0 a 7.0 b b 1.6 b 2 a 7 ab a 2.5 a Mean 2.0 a 6.5 b b 1.7 b 2 a 6.5 c bc 1.7 c Reference generation 2.0 a 8.0 a c 1.8 b 2 a 8 a b 1.8 ab * In a column the means are followed by the same letter are not significantly different at the 5% level by DMRT Adult stage: Moth longevity (pre-oviposition, oviposition and post-oviposition periods), to a certain extent, was affected by the larval diets (Table, 4). The maximal mean No of moth longevity (15 days) was recorded from moths resulted from larva reared on corn plants (4, 10 and 1 days) for pre-oviposition, oviposition and post-oviposition, respectively. On the other hand, the shortest period (10.5 days) of moth longevity was observed in S.A.1 (3, 6.5and 1 day). While, S.A.2 showed 13 days moth longevity (3.5, 8 and 1.5 days). Furthermore, the longest oviposition

9 Comm. Appl. Biol. Sci, Ghent University, 77/4 575 period (10 days) was recorded in the natural diet, while it was only 6.5 days in the artificial diet S.A.1 compared to 8 days in the artificial diet S.A.2. However, the post-oviposition period didn't differ in both (S.A.1) and the natural diet showing only one day but, it was increased to 1.5 day on the diet (S.A.2). The presented data shown in Table, (5) indicate the effect of the S.A.1and S.A.2 on the fecundity of the reared insect. The number of the deposited eggs increased with the progress of the 10 successive generations (G1:G10) from 256 to 352 and from 310 eggs to 389 eggs / female in the S.A.1and S.A.2, respectively. Whereas, the rate of the deposited eggs was gradually increased from 12 to 36 % in S.A.1 while, it was decreased in all generations of S.A.2 compared with those reared on the natural diet throughout the ten generations. Table (4). The effect of S.A.1 and S.A.2 on the moth stage longevity of the the European corn borer, Ostrinia nubilais Hub. Moth stage longevity (days) Generation S.A.1 S.A.2 Preovipositiooviposition Pre- Ovi position Postovipositiooviposition Ovi position Post- 1 St 3.0 a 7.0 a 0.0 a 4.0 a 7 c 2.0 a 2 nd 3.0 a 6.0 a 1.0 a 4.0 a 7 d 1.0 a 3 rd 3.0 a 6.0 a 1.0 a 4.0 a 8 c 1.0 a 4 th 3.0 a 6.0 a 1.0 a 4.0 a 8 c 2.0 a 5 th 2.0 a 7.0 a 1.0 a 3.0 a 8 c 1.0 a 6 th 3.0 a 6.0 a 1.0 a 3.0 a 9 b 2.0 a 7 th 2.0 a 7.0 a 1.0 a 3.0 a 8 c 2.0 a 8 th 2.0 a 7.0 a 1.0 a 3.0 a 8 c 2.0 a 9 th 3.0 a 7.0 a 1.0 a 4.0 b 9 b 1.0 a 10 th 3.0 a 6.0 a 0.0 b 4.0 b 9 b 2.0 a Mean 3.0 a 6.5 a 1.0 a 3.5 a 8 c 1.5 a Reference generation 4.0 b 10.0 b 1.0 a 4.0 b 10 a 1.0 a * In a column the means are followed by the same letter are not significantly different at the 5% level by DMRT Moreover the highest number of the deposited eggs/female was observed in females derived from larvae fed on artificial diet in G10 of S.A.2 (382) compared with (278) in G10 of S.A.1. The highest mean number of deposited eggs throughout the 10 generations was resulted from S.A.2 (358.2) while S.A.1 revealed the least number (304.4) versus was (400) from the natural diet. On the other hand, the number of hatched eggs/female (310.9) in S.A.2 compared to those resulted from S.A.1 (256.5 eggs) and the natural diet (320 eggs), successively. Meanwhile, the highest mean of hatchability percent was resulted from the artificial diet S.A.1 (92.58%) in the second generation compared to (91.93%) in S.A.2 and (80 %) in the natural diet.

10 Comm. Appl. Biol. Sci, Ghent University, 77/4 576 Table (5): The effect of (S.A.1) and (S.A.2) on the fecundity of the European corn borer, Ostrinia nubilais Hub. Adult fecundity S.A.1 S.A.2 Generation Hatched Hatched Laid eggs/female Laid eggs/female eggs/female eggs/female No. increase % No. % No. decrease % No. % 1 St nd rd th th th th th th th Mean Reference generation * In a column the means are followed by the same letter are not significantly different at the 5% level by DMRT In conclusion, the above mentioned results and literature declared that the S.A.1 could be considered a suitable artificial diet for a feasible mass rearing of the European corn borer, Ostrinia nubilalis Hub. The S.A.1 showed the shortest larval, pupal and life span for generation periods. Moreover, S.A.2 showed longer oviposition period (8 days) and higher mean of deposited eggs/female(358.5) and higher percent of egg hatchability/fertility(86.93) in comparison to SAD1 (6.5, and 83.92),consequently. In natural diet these values were ( 10, 400 and 80), respectively. The utilization of this artificial diet (S.A.1) will supply the researchers with the highquality insects in adequate numbers, at specified times and specific stages of development for the bioassay, toxicological and biological studies.

11 Comm. Appl. Biol. Sci, Ghent University, 77/4 577 REFERENCES ANDERSON T.E. AND, LEPPLA N.C. (1992). Advances in Insect Rearing for Research and Pest Management. West view Press; Boulder, Co, Xiii p. BARBULESCU A. (1996). Data obtained during on the mass rearing of Ostrinia nubilalis on artificial diet for several successive generations. Probleme-de-Protectia- Plantelor. 1996; 24(1): BARBULESCU A. (1998). Data obtained during on Ostrinia nubilalis Hbn. rearing on artificial diet in several successive generations. Probleme-de-Protectia-Plantelor. 1998; 26(1): BARBULESCU A. (1999). Different successive generations of Ostrinia nubilalis obtained by mass rearing on artificial diet. Probleme-de-Protectia-Plantelor. 1999; 27(1): 1-9. BARBULESCU A. (2001). Rearing of Ostrinia nubilalis specie in successive generations, on artificial diet, during Probleme-de-Protectia-Plantelor. 2001; 29(1): BENTI T. AND RANSOM J.K. (1993). Proceedings of the first National Maize Workshop of Ethiopia. 5-7 May (1992), Addis Ababa, Ethiopia. IAR/CIMMYT, Addis Ababa. BOHN M., FRIENDRICH H. AND MELCHINGER A.E. (1998). Genetic similarities among Winter wheat cultivars determined on the basis of RFLPs, AFLPs and SSRs and their use for predicting progeny variance. Crop Science.Vol.39 No CIMMYT AND EARO (1999). Maize production Technology for the future: Challenges and opportunities: Proceedings of the sixth Eastern and Southern 1998, Addis Ababa, Ethiopia: CIMMYT (International Maize and wheat Improvement Center) and EARO (Ethiopia Agricultural Research Organization). COSTAT SOFTWARE (1990). Microcomputer program analysis, version 4.20, CoHort software, Berkley, CA, USA. EL-METWALLY M.F., KHADR G.D., MOURAD S.A, MOHAMAD M.S. AND SALEH H.A. (1997). Mass rearing of Sesamia cretica Led. larvae on an artificial medium diet. Egyptian- Journal-of-Agricultural-Research. 1997; 75(3): KREPS R.C.,GUMBER R.K., SCHULZ B., KLEIN D. AND MELCHINGER A.E. (1998). Genetic variation in testcrosses of European maize inbreeds for resistance to the European corn borer and relations to line per se performance. Plant-Breeding, 117: 4,

12 Comm. Appl. Biol. Sci, Ghent University, 77/4 578 MASOUD M.A. (2005). The Influence of encoding Bt Corn Hybrids (MON 810 EVENT) on the infestation of the corn borers in Egypt. Egypt. J. Agric Res., 83 (2), 2005, pp MASOUD M.A., SAAD A.S.A., MOURAD A.K.K. AND GHORAB M.A.S. (2010). Mass rearing of the Pink Corn borer, Sesamia cretica Led Larvae, on semi artificial diets. 62 nd International Conference of Crop Protection May 18, Gent, Belgium. MESBAH H.A., MOURAD A.K., EL-NIMR H.M., MASSOUD M.A., ABD EL-AZIZ A.A. (2002). The role of some agricultural practices and fertilizer type on both the incidence of stem borers infestation and corn yield in Egypt. Mededelingen (Rijksuniversiteit te Gent. Fakulteit van de Landbouwkundige en Toegepaste Biologische Wetenschappen) 67 (3), pp ODINDO M.O AND ONYANGO F.O. (1998). Handbook of African cereal stem borers, economic importance, Taxonomy, Natural enemies and Control. Chapter (8): pp SALAMA H.S. AND TOLBA R.A (1971). Development of the sugar cane borer Sesamia cretica Led. On a semi-artificial diet. Zeitschrift-fur-Angewandte-Entomologie. 1971; 68(1): SEMEADA A.M. (1998). Single and combined effect of infestation with three corn borers on maize plants. Bull. Fac. Agric. Cairo Univ. 49: SESHU REDDY K.V. AND WALKER P.T. (1990). A review of the yield losses in graminaceous crops caused by Chilo Spp. Insect Science and its Application. (11), pp SINGH P. AND MOORE R.F. (1985). Handbook of Insect Rearing, Vol. I and II. Elsevier Science publishers, Amsterdam, the Netherlands. SONGA J.M., BERGVINSON D. AND MUGO S. (2001). Impacts of Bt-gene based resistance in maize on non-target organisms in Kenya. Characterization of target and non-target organisms of Bt-gene-based resistance in two major maize growing regions in Kenya. Insect Resistant Maize for Africa (IRMA). Annual Report, IRMA Project Document No.4. pp SOBEK E.A., MUNKVOLD G.P. (1999). European Corn Borer (Lepidoptera: Pyralidae) larvae as vectors of Fusarium moniliforme, causing kernel rot and symptomless infection of maize kernels. J. Econ. Entomol. 92: STEEL R.G.D. AND TORRIE J.H. (1980). principles and procedures of Statistic Abiometrical approach. 2 nd Ed.McGraw.Hill Kogahusha Ltd.pp.633.

13 Comm. Appl. Biol. Sci, Ghent University, 77/4 579 SZOKE C., ZSUBORI Z., POK I., RACZ F., ILLES O. AND SZEGEDI I. (2002). Significance of the European corn borer (Ostrinia nubilalis Hubn.) in maize production. Acta, Agronomica, Hungarica, 50: 4, WARUI C.M. AND KURIA J.N. (1983). Population incidence and control of maize stalk borers Chilo partellus (Swinh.) and C. Orichalcociliellus Strand. And Sesamia calamistis Hmps. In Coast Province, Kenya. Insect Science and its Application. (4), pp11-18.