Tinkering with saffron’s genetic makeup to develop climate resilience

  • Omics-based technologies, that aim to characterize biological molecules that make up a structure or function in an organism, are being used to modify the genomics of saffron for climate resilience.
  • Climate change impacts in the form of erratic rainfall and drought-like conditions affect the production of saffron in Kashmir valley.
  • Being a sterile species, saffron is not easy to breed, making genetic modification to create climate-resilient varieties challenging.

Sheikh Mohammad Sultan, a saffron grower in his sixties is uncertain about the future of the saffron industry in the Kashmir valley. Sultan and his family, while plucking saffron flowers, find the produce to have reduced in quantity. According to him, an area that used to yield 200 kg of saffron ore Crocus sativus now hardly produces 20 kg.

While there are varying reasons for the decline in production, climate change is considered a definitive one. According to a study by AM Husaini of the Division of Biotechnology at Sher-e-Kashmir University of Agricultural Sciences & Technology (SKUAST), unpredictable rainfall interspersed with drought is a major driver for the decline.

Saffron grows in limited areas as a niche crop. It is easily vulnerable to the impacts of climate change, potentially imperiling the livelihoods of thousands of farmers and traders.

Image shows a row of saplings
A fully bloomed and ready-to-harvest under-study saffron flower. Photo by Amir Bin Rafi

In order to address climate change impacts on saffron production, particularly the deficit of rainfall, new saffron varieties are needed. Genetic variations or subtle changes in the DNA (in saffron in this case) can help develop new saffron varieties. But saffron reproduces only vegetatively using corms or bulbs and cannot reproduce by generating new seeds (it is sterile). This sterility does not allow saffron to have genetic variations as seen in corn or other plants. Saffron cultivated worldwide is the same in terms of biological traits and varies slightly in size and shape depending on the environment.

According to Mehraj Ud Din, a senior scientist at the Advanced Research Station for Saffron and Seed Spices (ARSSSS) at SKUAST, modifying the genetics of saffron is challenging. As it is a sterile crop, its genetic variability induction (the variations in characteristics from which the most desired can be chosen for growing improved varieties) is very low.

Read more: Saffron, biodiversity and glaciers: Kashmir’s women scientists lead climate action

A 2020 study found that a large corm above eight grams produces three to four small daughter corms, which take several seasons to achieve the size and weight needed for flowering. Multiplication rates are extremely slow, and production further suffers when corms rot or become infected by diseases brought on by rodents and other sources – all contributing to commercial losses to a great extent.

Mehraj Ud Din says the inability of saffron to produce seeds is a major bottleneck in getting different variants (varieties). One can choose the varieties in other major crops according to one’s requirements. “We can do crossbreeding in the case of maize. There is a natural variability in other crops. However, it’s not the same with saffron,” he said.

The saffron grown in the valley has some natural mutants offering scope to tap those variations. Mutations are needed to get new saffron variants that are climate resilient. “Different types of mutagens are used to induce variability,” says Mehraj Ud Din.

ARSSSS is collaborating with Bhabha Atomic Research Center (BARC) in Mumbai and BARC Zakura in Kashmir, where the material is taken and exposed to varying radiations and then returned to be implanted in the center (ARSSSS). However, the exercise is a trial-and-error experiment. “We check which material has a good recovery rate by giving different doses to the material. But we don’t know whether we are getting any new mutants or if they only have a slight change.”

Image shows a row of saplings in pots
As part of a study, saffron is grown under different water conditions to check the water resilience. Photo by Amir Bin Rafi.

Building climate resilience using omics

To develop climate resilience, many studies on water adaptation and ideal temperatures for saffron are underway. To understand genetic variability between ecotypes of saffron across the areas of the valley where it is grown, researchers are looking for differences in adaptation to the differences in water availability.

“Currently, we are studying the water resilience of saffron by exposing it to different types of stress to see how plant growth is affected,” said Mehraj Ud Din, who opines that unusual rainfall is the primary reason for the decline in yield. “We believe there is a natural genetic variability in saffron in Kashmir. We are looking at which genotypes (varieties) will perform well under stress. If experiments yield any mutant, we study it in a controlled environment to check whether it will work.” He believes this may provide an alternative to the disturbed rainfall pattern.

Mehraj Ud Din says: “If we perform a mutation, the role of omics will be a facilitator – to identify the factor which has caused mutation. It shows which region is affected, where it is located, and how to exploit that if we go for genetic transformation.” Omics refers to a field of study in biological sciences that ends with -omics, such as genomics, transcriptomics, proteomics, or metabolomics. The ending -ome is used to address the objects of study of such fields, such as the genome, proteome, transcriptome, or metabolome.

Read more: Genomics offers clues to how forest trees responded to the last Ice Age

However, he further states that omics do not yield instant results. “We would like to have a flower of say 10-20 stigmas. But it’s not in our hands. The basic biology of saffron doesn’t permit that.”

Indoor farming of saffron is also being studied closely, particularly at temperatures required for the crop to be multiplied.

Asif M. Iqbal Qureshi, another scientist at ARSSSS, says saffron growers are keen on learning new ways to increase saffron yield. “To get more yield per unit area, we usually advise growers about saffron management, from the pre-production stage, where we tell them about the spacing, temperature, irrigation, to post-production, which includes advising them about flower picking, drying of stigmas and packaging.”

He further adds that to get more genotypes-saffron varieties that are climate resilient-mutation on a large scale is needed. Large swatches of land and significant manpower are needed to carry out the experiments in order to get desired results because one cannot predict which genotype fits well with specific climatic conditions. Qureshi says that the expectations of getting mutated genotypes are not high.

According to Mehraj Ud Din, even saffron lacks efficient mechanisms for induction, the industry is dependent on nature.

IMage shows saplings growing in a farm
A view of the Saffron grown inside the ARSSSS campus for study purposes. Photo by Amir Bin Rafi.

Banner image: A close-up of under-study saffron, grown in a regulated temperature at ARSSSS Pampore. Photo by Amir Bin Rafi.