TNAU Blackgram CO 6: A High Yielding Short Duration Variety

A high yielding blackgram culture COBG 653 is a cross derivative of DU 2 x VB 20 and matures in 60 - 65 days. This culture recorded an average yield of 877 Kg/ha with a yield increase of 24 per cent over the national checks varieties LBG 402 and LBG 17 under All India Co-ordinated trials. This was released for cultivation during rabi season in south zone consisting of Tamil Nadu, Andhra Pradesh, Karnataka and Odisha. In the state trials, it recorded an average yield of 733 Kg/ha with a yield increase of 13.46 per cent over VBN (Bg) 4, 12.42 per cent over VBN (Bg) 5 and 16.86 per cent over CO 5. It has bold seeds with a mean 100 seed weight of 5.5 grams. It is determinate and has synchronized maturity. It has good batter qualities like high initial batter volume and volume after fermentation. The protein content is 23.8 per cent. It is moderately resistant to mungbean yellow mosaic virus (MYMV), stem necrosis and root rot diseases. It is tolerant to aphids, stemfly and spotted pod borer infestation. This variety was notified recently as per the reference S.O. 632(E) dt. 25.03.2011. It is best suited for cultivation during rabi season in Tamil Nadu.

Blackgram (Vigna mungo (L.) Hepper) is a rich source of protein (20.8 to 30.5 per cent) with total carbohydrates ranging from 56.5 to 63.7 per cent.It is also a good source of phosphoric acid and calcium.It contains a wide variety of nutrients and is popular for its fermenting action and thus it is largely used in making fermented foods.Blackgram, cultivated as a sole crop and intercrop is the third important pulse crop in India, covering an area of about 3.24 milllion hectares and producing 1.46 million tonnes.Productivity is only 526 Kg/ha.In Tamil Nadu, blackgram covers an area of about 3.41 lakh hectares with production of 1.21 lakh tonnes and productivity of 355 kg/ha (Project Co-ordinator's Report, 2011, AICRP on MULLaRP).
The production of blackgram is mostly confined to the Asian countries as their tropical climates and soil type suit its cultivation.The largest producer of this pulse is India followed by Myanmar.But being the largest producer of blackgram does not take India to a comfortable situation, as it is also the largest consumer of the blackgram in the world and its total production is not able to fulfill its domestic consumption demand.The incapability of Indian production to satisfy its domestic demand makes it the largest importer of this pulse as well.In India, the major states that produce blackgram are Madhya Pradesh, Uttar Pradesh, Punjab, Maharashtra, West Bengal, Andhra Pradesh, Odisha, Tamil Nadu and Karnataka.The major constraints in achieving higher yield of this crop are lack of genetic variability, absence of suitable ideotypes for different cropping systems, poor harvest index and susceptibility to pests and diseases.Hence, breeding work was initiated to develop high yielding, short duration variety with synchronized maturity and to increase the productivity of the crop.

Materials and Methods
The blackgram culture COBG 653 was evolved at Department of Pulses, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore.This is a selection from the cross DU 2 X VB 20.Elite plants with desirable characters which contribute towards high grain yield were selected from F2 generation onwards.They were evaluated for their sustained performance, homozygosity and the culture COBG 653 was identified as the best.It was evaluated with check varieties in Multi location trial (MLT), Adaptive research trial (ART) , AICRP trials Viz., Initial varietal trial (IVT), Advanced varietal trial (AVT) and in on farm trials.Thus, a total of 106 trials were conducted.Besides, the reaction of the culture against important pests and diseases was studied.Based on the standard procedure the grain quality and its consumer acceptability were also analyzed.

Results and Discussion
The performance of the culture was tested in South Zone consisted of Tamil Nadu, Andhra Pradesh, Karnataka and Odisha during rabi season.It recorded an average grain yield of 826, 818, 913 Kg/ha in IVT, AVT 1 and AVT II trials,

Reaction to diseases and pests
The culture COBG 653 was tested for YMV reaction in Vamban and Coimbatore.At Coimbatore, it was found to be resistant both during rabi and summer seasons, whereas in Vamban the reaction was resistant/ moderately resistant (Table 2).This culture was also found to be moderately resistant to stem necrosis and root rot diseases (Table 3).A total of 106 trials were conducted to evaluate the culture COBG 653.It recorded an average yield of 733 Kg/ha, which is 13.46, 12.42 and 16.86 per cent yield increase over VBN(Bg) 4 , VBN(Bg) 5 and CO 5, respectively (Table 1).The culture COBG 653 was evaluated for spotted podborer and stemfly damage.It recorded less damage to spotted pod borer (2.1 per cent) and stemfly (12.0 per cent) when compared to check varieties.This culture had field tolerance to the above pests (Table 4 and 5).

Grain quality
Blackgram is mainly used to make fermented dishes.This culture has good batter characteristics with high initial batter volume and batter volume after fermentation ( Table 6).It has good organoleptic traits.It is nutritionally rich with high protein content of 23.8 per cent.

Morphological characters
The blackgram culture COBG 653 matures in 60 -65 days.It has erect growth habit with a plant height ranging from 30 -35 cm.Pods are glabrous and ranging from 40 -47 per plant.The seeds are bold, drum shaped, dull black with a 100 seed weight ranging from 5.0 to 6.2 grams (Table 7).
This culture COBG 653 is having superior features viz., high yield, short duration, synchronized maturity, non shattering of pods, bold seeds, good batter qualities and moderately resistant to important pests and diseases.Hence it was released as PU 30 (ch) 6.2