Trends of Major Cereal Productivity in South Asia

: The trend analysis in the time series of crop production is an important tool to make future plans and to take the appropriate decisions for sustainability in food production and future food security. The objective of this study was to assess the trend analysis of the yield of five different major kinds of cereal (paddy, maize, millet, wheat, and barley) from 1985 to 2018 in six South Asian countries (Nepal, India, Pakistan, Bhutan, Afghanistan, and Bangladesh). The average annual yields of cereals in five quadrennial drought years (1985, 1989, 1993, 1997, and 2002) were estimated. The results revealed that the yield of major cereals had an increasing trend over the study period. The reasons for the fluctuations in the production were due to the changing climates, increasing global warming, the development of new hybrids and cultivars, the adoption of new practices by the farmers, economic constraints, and agronomic constraints. For improving the production of cereal crops, the use of modern technology should be increased, and the agricultural organizations should provide full support at the country level.

The International Maize and Wheat Improvement Center (CIMMYT) is offering an advanced set of improved maize hybrids to partners in South and South East Asia and related agro-ecological zones, to enhance production for farmers in these regions [7]. Rampur-1, Makalu-2, P-3501, African tall, Kashmir gold, CH-124 are some of the maize varieties in South Asia. Wheat (Triticum aestivum L) consumption has been gradually rising since the green revolution in the 1960s now oscillating around 20 kg per capita per year in Bangladesh, 50-60 kg in Nepal and India; meanwhile, it has long been around 100 kg in Pakistan [8]. Wheat is the second major staple crop, next to the rice. A joint collaboration of National Agricultural Research Centers (NARC) and CIMMYT has made remarkable progress due to which significant increment in wheat production has been observed for the last few years (Chatrath et al., 2007). NL-30, Lumbini, Annapurna, VL-832, WH-896, Sehar-06, Lalma-13, Bajoka 2 BL, Bijoy are some of the wheat varieties grown throughout the region. Millet (Eleusine coracana L) has consistently been a valuable and nutritious part of the diets of small-scale farmers and indigenous groups in the region. Dalle-1, Okhle-1, Barnyard, Bari fox Tail, Bari Kaoun-3 are the millet varieties cultivated in different South Asian countries. Barley (Hordeum vulgare L) is cultivated in a very small area in South Asia. The majority of the world's barley is produced in regions where cereals such as maize and rice cannot be grown well [9]. This paper aims at finding out the drought years within the year of 1985-2018 and the total yield of cereals in the respective major drought years. Also, the ways of increasing the production of cereals in south Asia were described in brief. This will obviously help in projecting the future yield of the major cereals in South Asia.

Methodology 2.1. Socio-demographic and economic characteristics of the study area
The study was carried out in South Asia which is the association of eight countries. But the production of cereals was analyzed merely of the six countries (Nepal, India, Pakistan, Bhutan, Afghanistan, and Bangladesh. Two countries; Maldives and Srilanka, were excluded due to very low agricultural production compared to total production.

Figure 1. Map showing SAARC countries
South Asia comprises 1.9 billion populations within the area of 5.1 million km 2 . India is the largest contributor to the economy through GDP by the agricultural sector. The majority of the people are educated as the literacy rate of South Asia is 71%. Despite the constant advancement in the scope of occupations other than farming, agriculture is followed by most people as their primary profession. The socio-demographic characteristic of the different countries of South Asia is described below. Where TYn= Total yield for 'n' no. of years expressed in hg ha -1 (Hundred grams per hectare); TP= Total production; TA= Total area Annual average yield (AAY) is computed to determine the years of individual crops which have production below average as in equation (ii) AAY = (Total yield 1985 + Total yield 1986 … … … … … + Total yield 2018) (ii) No. of years Data analysis for yield was performed by using Excel ver.2020.

Individual cereal yield of cereals in South Asian countries
Data on cereal production may be influenced by a variety of reporting and timing differences. The total yield of different cereals from 1985-2018 in different countries of South Asia was presented in the Table 4.   1985, 1989, 1993, 1997, and 2002 was far less than the average yield which was 23154 hg ha -1 , 25976 hg ha -1 , 28080 hg ha -1 , 28302 hg ha -1 , and 28332 hg ha -1 respectively. The maximum yield of paddy was observed in 2018 which was 40243 hg ha -1 and minimum in 1986 which was 22281 hg ha -1 (FAO, 1985(FAO, -2018

National level total yield of cereals during drought years in South Asian countries
The total yield of cereals in Bhutan and Afghanistan was below average in all the years viz. 1985, 1989, 1993, 1997, and 2002 respectively. The average yield of Nepal, India, Pakistan, Afghanistan, Bhutan, and Bangladesh in five quadrennial drought years was presented in Table 6.