**3.15** *Caryedon serratus* **(Oliver) (Coleoptera: Bruchidae)**

**Identification:** Groundnut borer adult is 4 to 7 mm long, with small black markings on the elytra. It is readily distinguished from other pests of groundnuts by its very broad hind femur, serrate antennae and elytra that do not completely cover the abdomen (Ranga Rao et al., 2010).

**Life cycle and damage**: It is the only species that can penetrate intact pods to infest the kernels. Infestation of the harvested groundnuts can occur while the crop is being dried in the field, stored near infested stocks or crop residues. Females attach their eggs to the outside of pods or kernels and incubation period is about 4 to 6 days. The first instar larva hatches and burrows directly through the pod wall to reach the kernel, where the larva feeds and develops. Each larva feeds solely within a single kernel. A single larva can make a large excavation in the cotyledons, but no sign of damage is visible externally at this stage. Mature larvae emerge partially or completely from the pod and construct an oval papery cocoon. The life cycle of *C. serratus* is about 60 days under optimum conditions of 30°C and 70% r.h.

#### **3.16** *Bandicota bengalensis* **(Kok.);** *Rattus meltada pallidior* **(gray);** *Tatera indica* **(Hardwicke)**

Among the oil seed crops groundnut often suffers severe attack by rodents. Rodents damage both the standing crop and stored products. They damage the whole or the branches of the plant during burrowing and remove the pods at the mature and harvesting stages and take them into their burrows. *B. bengalensis* is the most predominant and widespread pest of agriculture in wet and irrigated soils. In dry land *T. indica* and then *R. meltada* are the predominant rodent pests. The chronic damage ranging from 2% to 15% persists throughout the country and severe damage, sometimes even up to 100% loss of the field crop (Ghewande & Nandagop, 1997).

**Control:** clean cultivation; proper soil tillage; crop scheduling; barriers; repellents and proofing are cultural techniques which may reduce rodent damages. Control weeds, which are an important component of the rodents diet. Apply rodenticides like poison baiting of rodents with zinc phosphide; and fumigation with aluminium phosphide are common in agricultural fields (Parshad, 1999).

#### **3.17 Crows (***Corvus splandens* **Viellot), Pigeons (***Columba livia* **Gmelin) and Black ibis (***Psaubis papillasa* **Temminck)**

Birds are relatively less important as pests of groundnut except pigeons and crows, which eat the freshly sown seeds leading to large gaps in the field (Ghewande & Nandagop, 1997). Brooks et al., (1988) assess 164 fields selected along road transects in Pakistan for vertebrate pests loss of groundnut. Lesser bandicoot rat (*Bandicota bengalensis* Gray) and the shorttailed mole rat (*Nesokia indica* Gray) were the most important. They often remove groundnut pods below ground without killing or otherwise damaging the plants. Also, the wild boar (*Sus scrofa* L.), desert hares (*Lepus nigricollis* Blanford); crested porcupines (*Hystrix indica*  Kerr) and house crows (*Corvus splendens* Vieillot) cause damage and loss to the crop.

Oilseed Pests 143

**Economic and action thresholds:** action threshold is observation of more than four to six

**Control:** thrips can be controlled biologically by pirate bugs, lacewing larvae, ladybirds, *Amblyseius cucumeris* (Oudemans) and *Amblyseius swirskii* (Athias-Henriot). If the threshold is exceeded application of systemic pesticides such as Dimethoate can reduce thrips

**Identification:** The soybean aphids are small, pale yellow with black cornicles and a pale yellow tail. Adults may be winged or wingless. Nymphs are smaller than adults and

**Life cycle and damage**: females usually lay eggs along the seams of the buckthorn bud. In the spring, nymphs hatch and aphids undergo two generations as wingless females on the buckthorn. The third generation develops into winged adults that migrate to soybean plants. The aphids then continue to produce wingless generations until the soybean plants become crowded with aphids and the plants experience a reduction in quality. Then, winged forms are produced to disperse to less-crowded soybean plants. There can be as many as 18 generations of aphids per year on soybeans. Males are only born in the fall so that the females and males can mate to produce the egg on buckthorn. Aphids suck the sap from leaves and stems of the crop. At high populations, aphids can cause the plants to abort flowers, become stunted, reducing pod and seed production and quality. Aphids also excrete honeydew, which can act as a substrate for grey sooty mould development. The

**Monitoring:** Monitoring should be done until the soybean is well into the R6 stage. Scout weekly; or as if the populations approach the threshold monitor more frequently (every 3-4 days). Monitor 20-30 random plants across the field and estimate the number of aphids per

**Economic and action thresholds:** The threshold is 250 aphids per plant and actively increasing on 80% of the plants from R1 up to the R5 stage of soybeans (OMAFRA, 2011).

**Control**: some of the soybean cultivars such as 'Dowling', 'Jackson', and 'Palmetto', showed resistance to aphids. Insidious flower bug, (*Orius insidiosus* (Say)), twospotted lady beetle (*Adalia bipunctata* L.), sevenspotted lady beetle (*Coccinella septempunctata* L.), the spotted lady beetle (*Coleomegilla maculata* De Geer), the polished lady beetle (*Cycloneda munda* (Say)), the multicolored Asian lady beetle (*Harmonia axyridis* (Pallas)), the convergent lady beetle (*Hippodamia convergens* Guérin-Méneville), and the thirteen spotted lady beetle (*Hippodamia tredecimpunctata* L.) can biologically control the aphids. Also, pathogenic fungi including *Pandora neoaphidis* (Remaud. et Henn.) Humber, *Conidiobolus thromboides* Drechsler, *Entomophthora chromaphidis* Burger et Swain, *Pandora* sp., *Zoophthora occidentalis* (Thaxter) Batko, *Neozygites fresenii* (Now.) Remaud. et Keller, and *Lecanicillium lecanii*, (Zimm.) Gams

wingless. Eggs are small, spherical and yellow when first laid but turn a dark brown.

soybean aphid may also be a vector of soybean mosaic virus (OMAFRA, 2011).

et Zare cause infection in an outbreak aphid population (Nielsen & Hajek, 2005).

**4.4** *Bemisia tabaci* **biotype B (Genn.) (Hemiptera: Aleyrodidae) Identification:** refer to the identification of *B. tabaci* in cotton section.

thrips per flower (Bailey, 2007).

plant in that field (OMAFRA, 2011).

**4.3** *Aphis glycines* **(Matsumura) (Homoptera: Aphididae)** 

population (Bailey, 2007).
