vk63@cornell.edu

Advisor: Robin Bellinder
Degree Program: PhD

Background:

I am from India. I earned my B.S. (1999) in Agriculture from CCS Haryana Agricultural University (CSS HAU) Hisar, India. I then went to Gent University, Belgium for doing my M.S. research in weed science with Dr. Robert Bulcke. I spent one year there and then i did my master course work in India at CSS HAU Hisar and earned M.S. degree (2002). My master's thesis title was "Response of grass weeds species to herbicides of different modes of action". In India, I worked with Dr. R.K. Malik. I came at Cornell in Janaury 2003 to pursue my Doctorate studies with Dr. Robin Bellinder (Prof. Weed Science).

Research:

My present research works emphasizes on the benefits and risks of herbicide resistant crops particularly rice and corn.

Corn project: Corn (Zea mays L.) is one of the major field crops grown in New York State and adoption of genetically modified (GM) herbicide resistant (HR) corn (Roundup Ready or glyphosate-resistant) varieties has been widespread. Although weedy relatives of corn are not found in the U.S., pollen flow with resultant contamination of organic fields is of major concern. Levels of contamination allowed in the EU markets are 0.9%. Hence, information is needed for NY state organic farmers, how far corn pollen can move and what are the cross pollination frequencies at different distance to minimize contamination well below EU adventitious threshold limit of 0.9%. Hence, in corn, we are looking at frequency and distance of gene flow from GM HR corn (Roundup Ready Corn) to conventional non-GM corn.

Rice project: Field trials for this project will be conducted in Haryana, India. The rice-wheat cropping system in India is one of the most important cropping systems for food security in the region, but this system is now threatened by stagnant yields in both rice and wheat and a declining trend in total factor productivity. The traditional method of growing rice by transplanting rice seedlings in puddled soils has an adverse impact on soil health and also creates problems with timely establishment of the succeeding wheat crop. Today problems such as natural resource degradation and increases in pest, weeds, and decline in water table have started to appear. The benefits of resource conservation technologies (RCTs) like zero-tillage (ZT) and bed planting have been documented in wheat and would be greater if used on the entire system i.e. both in rice and wheat. Weed management in rice needs to be addressed urgently in order to make RCTs more successful and to allow the benefits of ZT to be realized in wheat which otherwise is lost due to puddling soil for rice.

Herbicide resistant rice would dramatically overcome weed control problems in direct seeded (DS) ZT rice and would stop the annual cycle of puddling and pulverizing the soil. In our project we will use imidazolinone-resistant rice (IMI-rice) which conveys resistant to imidazolinone group of herbicide and is not a transgenic crop as it was developed by traditional mutation breeding method, hence may result in faster consumer acceptance. Imazapyr is a broad spectrum imidazolinone herbicide and has both soil and foliar activity on numerous weeds. Benefits that would come from the direct-seeding or bed planting combined with ZT includes reduced natural resource depletion, simplified weed management, reduced environmental impact (less green house gas emissions and soil degradation), higher yields and profits, improved livelihoods, and improved quality of life for farm families. The overall aim of this project is to develop a sustainable system of zero-till (ZT) direct seeded rice that maintains yield, decreases water use, and improves weed management in Northwestern India. The specific objectives are: (1) to evaluate IMI-rice under three tillage systems currently being used or encouraged in the region: ZT, bed planting and the conventional transplanted puddled rice system; (2) to determine appropriate herbicide programs for weed control in direct seeded ZT IMI-rice; (3) to determine the critical weed free period needed for direct seeded ZT rice; and (4) to identify and quantify the potential risks associated with the introduction of HR rice due to gene escape via pollen from HR rice to weedy relatives.