February 2010

FAI-IPI 6^th Round Table Conference on "Enhancing Nutrient Use Efficiency through Potassium"

A Round Table Conference on "Enhancing Nutrient Use Efficiency through Potassium" on 9^th February, 2010 in New Dehli was co-organised by the International Potash Institute (IPI) and The Fertiliser Association of India (FAI).

Thirty scientists and representatives from the Indian Council of Agricultural Research (ICAR), State Agricultural Universities, Planning Commission, Ministry of Agriculture, International Plant Nutrition Institute (IPNI), Potash Research Institute of India (PRII), International Zinc Association (IZA), and the Indian Fertiliser Industry participated in the event. Mr. S. Chander, Director General, FAI, New Delhi welcomed the participants, Mr. H. Magen, Director, IPI, Switzerland gave an introduction to the program, and Dr. P.S. Gahlaut, Managing Director, Indian Potash Limited (IPL), New Delhi delivered the opening remarks.

Mr. Chander highlighted various FAI programs implemented in collaboration with international organizations during recent years. The current FAI-IPI Round Table Conference is one such ongoing program and is the sixth in the series. Earlier Round Table events were organized at Chandigarh, Pune, Chennai, Bhubaneswar and Lucknow.

The need for improving agronomic efficiency of plant nutrients, which was reported to be declining over the years in India, was emphasized by Mr. Magen. There are a number of factors which affect nitrogen use efficiency (NUE). However, he stated that NUE could be increased by 20 percent by promoting best management practices. He drew delegates' attention to the program of four specific papers on NUE, stating that they should provide opportunities for discussion on the factors involved in the decrease in agronomic efficiency of plant nutrients in both irrigated and rainfed agricultural systems in India. Hillel expressed a hope that deliberations and discussions would be focused on the objectives of the program and that answers and recommendations on the questions being faced would emerge.

In his opening remarks, Dr. Gahlaut stated that efficient use of fertilizers was of critical importance because raw materials for fertilizers are finite and declining availability is predicted. The situation for potassium is somewhat better. As a group, there should be concern for agricultural sustainability and the welfare of agriculture and farmers. Dr. Gahlaut pointed out that the rising cost of fertilizers was inevitable but fertilizer use by farmers had to be profitable in all cropping systems. Raising concerns about stagnation in agricultural production, he mentioned that enhancing crop productivity was a necessity to meet the food demand for an ever increasing population. He stated that an appropriate benchmark, which was deemed achievable for farmers, should be fixed. Dr. Gahlaut added that potash (K) has been used in India since before independence. A company called Indian Potash Limited (IPL) was created by the Government of India with a mandate to promote balanced fertilization and to establish potash requirements. He mentioned that thousands of experiments had been conducted to highlight the benefits of potash in improving crop yields and quality. He informed the delegates that potash use has been accepted by farmers but they need continued support with knowledge on nutrient management in various cropping systems and conditions. With enhanced NUE, through potash application and better protection of crops from various plant pests, farmers can save thousands of rupees on pesticides by optimized use of potash. The use of potash will go a long way in improving the environment. He expressed his hope that the Round Table would help in taking the best available knowledge to farmers.

Four papers were presented to the delegates:

1. Yield potential of rice and wheat in Indo-Gangetic plains by Dr. P.K. Aggrawal, National Professor, Indian Agricultural Research Institute (IARI), New Delhi.
2. Analyzing nitrogen use efficiency in long-term experiments in irrigated wheat and rice by Dr. A. Swarup, Head, Division of Soil Science and Agricultural Chemistry, IARI, New Delhi.
3. Analyzing nitrogen use efficiency in long-term experiments in rainfed crops by Dr. Ch. Srinivasa Rao, Principal Scientist, Central Research Institute for Dryland Agriculture (CRIDA) Hyderaba.
4. N & K interaction in potato by Dr. S.P. Trehan, Principal Scientist, Central Potato Research Station (CPRS), Jalandhar.

Each paper was followed by extensive discussion.

In the concluding session, Mr. Chander requested participants to provide their recommendations. Summing up the session, he mentioned that current potash consumption in India was 1 mt less than the requirement for sustainable food production. Use of potash should be promoted where it is currently underutilized. Consideration for all limiting nutrients is required to achieve optimum yields. He added that integrated nutrient management is essential to improve soil health and crop productivity.

Mr. Magen provided some concluding remarks. He informed delegates that the idea of the Round Table had come out of the IFA agronomic workshop on "Fertiliser Best Management Practices (FBMPs)" held in Brussels, Belgium in March, 2007. In addition, he cited the papers of Dr. P.D. Sharma and Dr. P.P. Biswas on "A New Approach for Estimating Fertilizer Response Ratio - the Indian Scenario" published in the Indian Journal of Fertilizers, and the research of Dr. P.K. Aggrawal, as further sources for preparing this Round Table. Mr. Magen felt that while NUE in irrigated rice and wheat in the Indo- Gangetic Plains can be calculated from experimental results, this information was lacking in rainfed areas, and hence, called for more systematic long-term research in rainfed areas. He observed that the data on recovery efficiency (amounts of nutrients taken by plants) was lacking in the papers presented, and were needed to better understand other aspects of NUE. He also mentioned that Dr. P.K. Aggrawal in his presentation on "Yield Potential of Rice and Wheat in Indo Gangetic Plains" had set the tune excellently and provided a realistic yield target for irrigated rice and wheat production. However, he stated that work on yield potential in rainfed crops was not presented at the meeting, and needs to be further explored. Finally, Mr. Magen requested delegates to take away key messages according to their own area of interest. For example, he stated that key messages for him included the importance of NUE and the environmental benefits it brings. He thanked all the speakers for their presentations and all the participants for their active participation in the discussion, as did Dr. R.K. Tewatia in the final vote of thanks.

Conclusions and recommendations
Some of the major conclusions and recommendations that emerged from presentations and discussions during the conference are highlighted below:

1. The gap between the average production and attainable yield of rice and wheat is very high in the Indo-Gangetic plain, especially in the eastern region. To bridge the gap, assured availability and application of inputs and their efficient management through educating the farmers are required. Dr. Aggrawal stated that there was a yield gap of approx 2 mt ha^-1 between actual and attainable yields. More than half (56%) of this gap could be attained by efficient nutrient management.
2. The results from the long term fertilizer experiments show that Integrated Plant Nutrition Systems (IPNS) is the right approach to improve soil health as well as enhance NUE. Application of FYM at 10-15 mt ha^-1 (when available) along with soil test-based NPK application, usually improves sustainable production in different cropping systems and different soil types.
3. The effect of potassium on NUE in irrigated cereal-based systems was well presented by Dr. A. Swarup through meticulous analysis of longterm fertilizer experiments in various parts of India. The agronomic efficiency of nitrogen (AEn) could be significantly enhanced through the appropriate use of P and K. Addition of P and K over N alone increased AEn, which varied from 85% in wheat to 67% in summer rice. Clearly, these long-term experiments provide an excellent tool to diagnose and plan for better nutrient management in cereal-based cropping systems.
4. Potassium plays a key role in balanced fertilization in both rainfed and dryland areas. However, as presented by Dr. Ch. Srinivasarao, the average use of potassium in these areas is rather low as compared to irrigated areas. Considering the role of potassium in alleviation of water stress in plants, it should be promoted in rainfed and dryland areas. The forum also stressed the need to include K treatments in longterm fertilizer experiments being conducted in rainfed/dryland agriculture. The lack of these treatments prevents systematic evaluation as conducted in long-term fertilizer experiments on irrigated land.
5. The positive interaction effect of N x K has been observed in cereals and other crops like potato. This positive interaction effect needs to be optimized through adequate application of K over N application to further improve NUE.
6. Potato cultivars showed wide variation in agronomic use efficiency (AUE) of N and K. The hybrid JX 576 had the highest AUE of N & K among the cultivars tested. It showed about 15-24% greater AUE of N & K than the best control, Kufri Pukhraj. Farmers are to be advised to cultivate suitable varieties to achieve higher NUE.
7. Potassium recommendations need to account for soil type, available K, type of crops and the agro-climatic zone. The integration of all these factors will lead to improved potassium fertilizer recommendations.
8. On the basis of an ideal ratio of nutrient use (4:2:1), which can be used as a general guideline, it is observed that there is gap of about 1 million mt of K between current consumption and that required for adequate food production in India. Therefore, an additional supply of potash fertilizer needs to be provided in the future to enable optimized nutrient management in Indian agriculture.