**4. Constrains**

Cereal (in fact rice) agriculture is synonymous with Bangladesh agriculture that plays a key role in food security and livelihood. Only 92 cropping pattern out of existing 316 was identified as an exclusive non-rice area which occupied less than 9 per cent of the net cropped area of Bangladesh [7]. The cereal agriculture,

and agriculture in Bangladesh as a whole, is facing serious natural and man-made hitches that deserve special attention to this sector. The arable land is decreasing at an alarming rate (0.1% yr.−1) due to urbanization, roads and highways, infrastructure development, etc., severe degradation of natural resources like soil, water, climate, etc., the recurrent occurrence of devastating flood and drought, and the looming threat of salinity increment in the coastal region. Further in Bangladesh condition, the global climate change and related adverse effects on agriculture are rendering the worst impacts in temperature rise, abnormal rainfalls, sea-level rise, frequency of cyclone and storm surges, the encroachment of more saline areas, aggravation of drought problem and reduction in the availability of surface and groundwater [29]. There is a substantial extent of degradation of agricultural lands caused by soil erosion (1.70 m ha), river erosion (1.70 m ha), soil fertility decline (8.00 m ha), depletion of soil organic matter (7.50 m ha), waterlogging (0.70 m ha), soil salinity (0.84 m ha), pan formation (2.82 m ha), acidification (0.06 m ha) and deforestation (0.30 m ha) [30]. Some other soil-related constraints to cereal crop production are heavy consistency, poor structure, high osmotic pressure or drought, both physical and physiological, causing a reduction in the ability of plants to absorb water and nutrients, etc. The soil health scenario becomes worsen due to imbalanced fertilization and unplanned increase in mono-crop based cropping intensity and thus, the quality agricultural land is getting scanty. A survey reported that 2% of arable land belongs to a very good type, 34% good, 39% moderate, 16% poor, and 9% very poor [30].

The quality and timely supply of agricultural inputs are other constrain for cereal crop cultivation in Bangladesh. For instance, about 18% of the entire seed requirement of the country can only be met from certified and truthfully labeled seeds of Government and private sources, and the remaining 82% comes from the seed storage of farmers' own. There are serious problems in the quality of seeds supplied by public, private, and farmers themselves [30]. The scarcity of irrigation water (and its resources) is added to another constrain for sustainable cereal production in Bangladesh and the world as well. For example, an increase in Boro growing area in Bangladesh to 6 m ha by 2050 will increase the irrigation demand to *ca*. 40 k m3 from the current demand of *ca*. 31 k m3 ; global warming may further aggravate the demand by about 3% for dry climate change scenarios [31]. Groundwater is the primary source of irrigation and supplies about 80% of the water requirement of the total irrigated area of the country [16]. There is nonregulated and excessive use of groundwater and limited effort to augment surface water. Moreover, water use efficiency is also poor at the farm level. The over-use of groundwater is most evident in a small sub-region known as the Barind Tract; this increased demand will further deplete the groundwater resources. The quality of irrigation water also comes forward as another constrain for agricultural productivity in Bangladesh because of water pollution due to the presence of arsenic, heavy metals, salts, agrochemicals, industrial wastes, etc. A countrywide campaign is, therefore, required to conserve water and use it judiciously and institute a proper land use planning system. Mandatory rainwater harvesting and water use efficiency deserve higher priority.

#### **5. Challenges**

Bangladesh, one of the highest densely populated country in the world, endures the 8th largest world population (*ca*. 164 m) which has been estimated to increase 186 and 202 m by the years 2030 and 2050, respectively [32]. One of the major challenges of cereal agriculture in Bangladesh is to produce more food, to feed this

#### *Cereal Grains of Bangladesh – Present Status, Constraints and Prospects DOI: http://dx.doi.org/10.5772/intechopen.97072*

ever-increasing population. Other major challenges of cereal (crop) agriculture are to raising productivity and profitability, retaining sustainability, increasing resource-use efficiency, conserving natural resources and increasing land and water productivity, improving product quality and developing marketable production, improving post-harvest management, meeting demands for diversification and commercialization of agriculture [6]. The other emerging challenges include shrinkage of agricultural land every year due to urbanization, infrastructure development, roads, etc. The land quality is also deteriorating due to soil fertility degradation (e.g., nutrient imbalance, low organic matter, etc.), soil erosion, soil and water pollution, and increased soil salinity.

Due to climate change, sea-level rise will cause inundation of about 16% of total cropped area, displace 10% of the population, increased salinity in the coastal zone and reduce crop yields, ultimately causing loss of 2 m t of crop harvest [29]. Global warming will cause cyclones and storm surges in high frequency and volume. Due to river erosion and storm surges, moderate to severe erosion will occur in flood plains and char lands. Out of 2.85 m ha, about 1.00 m ha in the coast is affected by different degrees of salinity which will continue to increase due to climate change. About 2.32 m ha and 1.2 m ha of net cropped area are respectively severely and moderately drought-affected and the problem will further aggravate. Moreover, about 1.32 m ha and 5.05 m ha of the net cropped area are, respectively severely and moderately flood-prone that seriously hamper crop production [29]. Besides, reduced availability of surface and groundwater in the dry season due to excessive extraction of groundwater for irrigation purposes is coming up as a serious problem. The development of water-saving techniques in agriculture is a critical issue. The inadequate facilities and programs for the production and distribution of quality seeds and other inputs to the farmers are the main reason for low productivity; there is a wide yield gap between demonstration and farmers' field yield. For example, the current yield gaps between demonstration and farmers' yield for Aus, T. Aman and Boro are 2.74, 4.89 and 4.08 t ha−1, respectively [29]. Thus, the challenge is to reduce the current yield gap for cereal production enhancement. The farmers' knowledge-gap in adopting modern agricultural technologies also leads to low productivity. Further, the yield ceiling of modern cultivars needs to be improved by developing super cultivars. Low quality and adulterated agricultural inputs *viz*. fertilizers and pesticides, marketed by unscrupulous traders and absence of farm gate price support for the producers are a few of several other challenges that exist in the cereal agriculture and crop subsector as well. The low level of mechanization serves as a huge impediment towards cereal production, which in turns, results in a high cost of production for these crops. The creation of adequate institutional development in the areas with poor infrastructure, research funds and facilities, and skilled manpower for the adoption of innovative agro-technologies is also an emerging challenge in the agricultural sector.

### **6. Prospects**

Although Bangladesh faces huge constrains and challenges in achieving food and nutritional security due to its high population, diet changes, and limited room for expanding cropland and cropping intensity, Bangladesh will remain self-sufficient in rice at least to 2050 at the present rate of technological, in both cultivar and management, advancement and population growth [16]. The Intergovernmental Panel on Climate Change estimates, on contrary, reported that the rice production in Bangladesh could decline by 8 per cent and wheat by 32 per cent due to higher temperatures and changing rainfall patterns by 2050 [33]. For achieving food and

nutritional security in the coming days, the following actions may be taken to increase cereal grains yield (per unit area) and production –


and establish a database for indigenous technologies owned and practised by the rural farming community [37].


The major cereal grains, *viz*. rice, wheat, and maize, make up a critical portion of many diets, and cereal-based foods are a major source of energy, protein, B vitamins and minerals for the world population. However, these possess a lower concentration of mineral elements (micro and macro-nutrients) which caused the hidden hunger due to micronutrients deficiency [38]. The inclusion of mineral nutrient-rich minor cereals in the everyday diet might also be helpful to meet the mineral requirements and to fight against the related problems.
