This study was conducted to investigate a cheap and readily available alternative control measure for cassava anthracnose disease causal agent (Colletotrichum gloeosporioides f. sp. manihotis), through the use of antimicrobial crude plant extracts such as neem (Azadirachta indica), bitter leaf (Vernonia amygdalina), Ocimum gratissimum and Xylopia aethiopica, on the fungal growth parameters (mycelial growth, sporulation and germ tube development). The extracts at concentration levels of 25, 50, 75 and 100% full strength concentration showed an inhibitory effect on mycelial growth, germ tube development and sporulation of fungal isolates 05FCN, 10FCN, 12FCN and 26FCN. Neem seed and leaf extracts at 100% showed a total reduction in sporulation in most of the fungal isolates. The inhibitory properties of the plant crude extracts indicated a promising control option for consideration in cassava treatments of planting stocks, particularly in areas where farming is at a basic subsistent level, and less available money to meet the high cost of pesticides.

An experiment on efficacy of insecticides against Heliothis armigera (HB.) was conducted in the field of Entomology Section, Agriculture Research Institute, and Tandojam during 1998. One and half month old seedlings of tomato variety Pomodor were planted in a four replicated randomized complete block design, each replication comprised of eleven row & of six meter long while row to row distance was 75cm. Seven insecticides, namely Karate, Ambush, Cymbush, Ripcard, Mavrik, Baythroid and Sherpa were mixed with water and sprayed on the crop with the help of hand operated Gloria sprayer. The pretreatment larval population counts were made one day before of each spray, whereas post treatment population counts were made after 24, 48, 72 hours, and one and two weeks after treatment. It was found that all the insecticides provided significantly effective in controlling fruit worm of tomato in both the sprays. Among various insecticides tested Karate (2.5 EC) and Bathroid (5 EC) were more effective in controlling tomato fruit borer in both the sprays. However, Ripcard (10 EC), Ambush (10 EC), Cymbush (5 EC), Mavrik (2 EC), and Sherpa (5 EC) were also found to be effective. The results were statistically highly significant. The pattern of insecticides after 24, 48, 72 hours and one and two weeks of spray remained more or less same. On over all basis Karate and Baythroid found to be superior to all the insecticides under trial in controlling the pest. Besides that, it was observed that the insecticides showed a gradual decline in their effect (less reduction in the pest population) one week after the treatment and onward.

An experiment on rice (Oryza sativa L.) was conducted in clay-loam soil during the boro season (1995-'96) to study the bio-efficacy of some new generation herbucudes on summer rice at University Teaching Farm, Mondauri, B.C.K.V., Nadia, West Bengal, having ten treatments with three replications fitted in a Randomised Block Design. This results of the experiment revealed that the lowest weed population (at 60 DAT) of 19.33/m2 and lowest weed dry weight (at 60 DAT) of 10.70 g/m2 was exhibited by T9 (hand weeding twice at 20 and 40 daus after transplanting) being statistically at par with T7 (Anilophos 18 EC + 2, 4-D Na salt 80% a.i. @ (375+350) g a.i./ha) showing 25.00/m2 weed population (at 60 DAT) and 13.86 g/m2 weed dry weight (at 60 DAT). But highest grain yield (50.74 q/ha) was obtained with T7. That is why anilophos 18 EC + 2, 4-D Na salt 80% a.i. @ (375=350) g a.i./ha showed the best performance in relation to weed control and weed dry weight resulting maximum grain yield which, however, was found statistically at par with the treatment hand weeding twice at 20 and 40 DAT (grain yield - 50.48 q/ha) and Butachlor 50 EC @ 1.5 kg a.i./ha (grain-yield 48.92 q/ha) and Butachlor 50 EC @ 1.5 kg a.i./ha (grain-yield 48.92 q/ha). Unweeded control (T10) performed the worst.

Six different fungicides, i.e. Ridomil MZ 72 WP, Antracol 70 WPM, Liromanzeb 80 Dithane M 45 WP, Polyram Combi and Cupravit were tested against downy mildew disease of onion caused by Peronospora destructor Berk in the field under artificially created disease pressure for two consecutive years (1994-95). Ridomil MZ 72 WP was found to be the most effective fungicide followed by Antracol 70 WP, Liromanzeb 80 Wp and others. These fungicides also increased the onion yield by 33-73% over the control. This yield increase was 73% in case of Ridomil MZ 72 WP, while in Antracol 70 WP and Liromanzeb 80 WP it was 66%. It was 40% in Dithane M 45 WP but in Polyram Combi and Cupravit yield obtained was 33%.

In order to evaluate the efficacy of SPICTURIN(R) (Bacillus thuringiensis var. galleriae) and HaNPV against H. armigera on chickpea, two field experiments were carried out at Kurumpapalayam and Saravanampatti in Coimbatore district during summer 1997. In both the field trials, chlorpyriphos @ 1.00 1/ha proved its superior efficacy in recording the lowest larval population and pod damage followed by Spicturin @ 2.00, 1.50 and 1.00 1/ha each combined with HaNPV three and seven days after each spray and also at harvest. The highest pod yield was recorded in chlorpyriphos @ 1.00 1/ha followed by Spicturin @ 2.00 1/ha ha+HaNPV which were on par as against in untreated check. The cost: Benefit ratio was higher in chlorpyriphos 1.00 1/ha (1:3.50) followed by HaNPV @ 1.5x1012 POB/ha individually (:3.32), Spicturin @ 1.00 1/ha (1:2:18) and Spicturin @ 1.00 1/ha+HaNPV (1:2.07).

Root-knot nematode Meloldogyne javanica has wide spread and high losses on tomato fields in Bushehr provinoe. Limitations of methyl bromide use were causes we will find alternatives. Basamid (Dazomet) acts as nematicide. In this research we applied three amounts of bas amid 20, 30 and 40 g/m2 as original treatment, one amount of methyl bromide 50 g/m2 and control. All treatn1ents were used in soil one month before cultivation of tomato seedlings and soil surface were covered with polyethylene plastic. Project were designed to four treatment, three replication in randomized completely block design. Comparison of means were earned out with Duncan test. Basamid treatments, methybromide and control were in one level as control of nematode population. More .research need for evaluate of effect of polyethylene plastic cover in control of nematodepOpu1a!ion. ...... Key words: Nematode, Nematicides, Tomato, Meloidogyne javanica, Basamid and Dazomet

A total of eighty buffalo calves were immunized against HS vaccines. Alum precipitated HS vaccines and oil based HS vaccine procured from different sources were used. The immune status of animals was studied using indirect haemagglutination test (HIA) and mouse protection test. The sera of the animals were examined for HIA titres on day zero (before vaccination) and thereafter on 15th, 30th, 45th, 60th, 75th and 90th day post Vaccination. All the test gave zero titre on day 0. A very poor immune response (GMT 2.1, 4.3, 2.8 and 2.1 for vaccines of NIAB, VRI, HPL and SPV, respectively) was observed on 15th day post vaccination. Maximum HIA geometric mean titre alum precipitated vaccines of VRI, HPL and SPV GMT 64, 64 and 52, respectively were recorded on 45th day post vaccination. Thereafter a decline in the titre commenced and titre recorded on 90th day for VRI, HPL and SPV were GMT 22.6, 22.6 and 14.9, respectively. The sera of animal vaccinat ed with oil based HS vaccine of NIAB showed high antibody titer than alum precipitated HS vaccines. The increase in antibody titre was gradual up to 90th day post vaccination. The HIA GMT was 73.3 on 45th day post-vaccination but titre was increased up to 90.5 on 90th day post vaccination. The sera having HIA titre of 1:16 and above protected 100% of challenged mice. The sera having titre 1:8 protected 80% challenge mice, but the sera with HIA titre 1:4 conferred no protection to the passively immunized mice. Furthermore, control animals lost their lives in response to challenge inoculum as 100% mortality was recorded. A strong relationship between HIA titre and mouse protection test was found. The oil based HS vaccine give better and long lasting immunity up to a period of 90 days. The alum precipitated vaccines gave a dismal picture and necessitates attempt for its improvement and switching over to other vaccines which may give long lasting immunity.

Comparative efficacy of five insecticide combinations i.e. Match + Profenophos, Polytrin-C, Polo + Arrivo, Baythroid TM and Karate + Endosulfan were applied against bollworm complex of cotton during 1999. The results indicated that all the insecticides were effective in controlling the bollworm. The insecticide combination Match + Profenophos was most effective followed by Polytrin-C, (Polo + Arrivo), Baythroid TM and (Karate + Endosulfan). It is recommended that the out break of the bollworm complex can easily control with the application insecticide name Match, Profenophos.