35-Day Dry Spell in Rajasthan: Can Climate-Resilient Moth Bean Varieties Protect Farmers?

Farmers in India’s dry regions increasingly have to manage longer gaps between rainfall events. For rainfed crops, even a few weeks without rain during flowering or grain formation can reduce yields sharply. A recent field assessment in western Rajasthan shows how crop varieties bred for moisture stress can help farmers handle such conditions.

ICAR-Central Arid Zone Research Institute has reported strong performance from four moth bean varieties during Kharif 2026. CAZRI Moth-4, Moth-5, Moth-6 and Moth-7 continued growing after rainfall stopped and survived a dry spell lasting about 35 days.

Moth bean is an important pulse crop in the hot arid regions of western Rajasthan. It is cultivated across nearly 10 lakh hectares, but average productivity remains low at around 350 kg per hectare because rainfall is limited, uncertain and unevenly distributed.

ICAR-CAZRI reports that the region normally receives only about 150–250 mm rainfall, while dry spells of 20–30 days are common. Such conditions make moisture availability one of the biggest constraints for farmers growing rainfed moth bean.

The 2026 season provided an unusually demanding test. During crop growth from 10 July to 2 September, cumulative pan evaporation was about 317 mm. After rainfall on 3 August, the crop went through a prolonged rainless period extending into September.

How Did the Moth Bean Varieties Perform?

According to CAZRI, rainfall stopped after 3 August 2026 and the crop experienced a 35-day dry spell from 3 August to 7 September. During this period, cumulative pan evaporation reached around 180 mm, increasing the pressure on available soil moisture.

The crop had received useful rainfall during its early growth stages. An 86-mm rainfall event on 2 August helped maintain surface soil moisture, which was recorded at around 15–16% by volume in the upper 0–10 cm soil layer.

CAZRI linked the varieties’ performance to early canopy development, soil binding and moisture retention around the roots. These characteristics helped the plants maintain growth and reproductive development despite the extended absence of rainfall.

CAZRI has been working on moth bean breeding to develop varieties with greater developmental flexibility, stress resilience and yield potential for harsh arid environments. Four varieties, CAZRI Moth-4 through Moth-7, were released during the past three years.

Their performance in 2026 is important because the crop encountered moisture stress during an actual farming season rather than only under controlled experimental conditions. Field performance can provide useful evidence about how varieties respond to unpredictable rainfall patterns.

This does not mean every farmer will get the same result. Soil type, sowing date, seed quality, rainfall distribution, weed pressure and crop management can all affect the performance of a drought-resilient variety.

Why Does This Matter Under Climate Change?

Climate change does not simply mean less rainfall everywhere. One major agricultural risk is greater variability, including intense rainfall followed by longer dry periods. Rainfed farmers are especially exposed because they have limited ability to replace missing rainfall through irrigation.

India has already assessed climate vulnerability across 651 predominantly agricultural districts under NICRA. The government identified 310 districts as vulnerable, including 109 classified as very highly vulnerable and 201 as highly vulnerable.

The government has also prepared District Agriculture Contingency Plans for these districts. These plans recommend location-specific crops, varieties and management practices for dealing with weather aberrations, giving farmers and state agriculture departments a framework for responding to climate risks.

Farmers in rainfed areas can reduce exposure to dry spells by selecting varieties suited to their local agro-climatic conditions. Choosing the right crop duration and sowing time can also help the crop avoid the most damaging period of moisture stress.

Soil moisture conservation is equally important. Farmers can use practices such as timely interculture, residue management where suitable, field bunding and other locally recommended moisture-conservation measures. The objective is to retain available rainfall for longer rather than allowing it to disappear quickly through runoff or evaporation.

Crop diversification can provide another layer of protection. Depending on local conditions, farmers can combine drought-tolerant pulses with other suitable crops instead of depending entirely on one crop whose performance may collapse under prolonged moisture stress.

Should Farmers Switch to New Varieties?

Farmers should not change varieties solely because a crop has performed well during one difficult season. A variety needs to be evaluated for yield, maturity period, disease response, seed availability, market demand and suitability to the local soil and rainfall pattern.

Farmers should first consult their local Krishi Vigyan Kendra, agriculture department or agricultural university before obtaining seed. Recommended varieties can differ between districts, and seed should come from recognised sources rather than unverified sellers.

For farmers already growing moth bean in Rajasthan’s arid and semi-arid regions, the performance of CAZRI Moth-4, Moth-5, Moth-6 and Moth-7 provides a useful reason to ask extension officials whether these varieties are suitable for their particular location.

Climate-resilient varieties are one tool, not a complete solution. A variety can tolerate moisture stress better, but it cannot compensate indefinitely for severe drought. Water conservation, soil management, timely sowing, crop diversification, weather advisories and access to quality seed still matter.

The Rajasthan experience shows why crop breeding is becoming increasingly important for climate adaptation. When rainfall becomes less predictable, farmers need varieties that can maintain growth through short or prolonged periods of stress.

For rainfed farmers, the practical lesson is to prepare for rainfall uncertainty before the season begins. Selecting a locally recommended resilient variety and combining it with moisture-conservation practices can improve the chances of maintaining a crop when rainfall does not arrive as expected.