Exploring the diversity of rice landraces in Godavari zone of Andhra Pradesh

Introduction

Rice is the primary food source for over two billion people worldwide, particularly in Asia, where it provides 40-70% of the total food calories consumed. Despite the Green Revolution's significant increase in rice yields, poverty and hunger persist. In recent decades, rice yields have stagnated, and traditional rice varieties have been replaced by highyielding varieties. In India, over 200,000 indigenous rice varieties are cultivated, but many are facing extinction. conserving these desi rice varieties is crucial for ecological importance viz., biodiversity, climate resilience and management soil health. The have socio-cultural importance like cultural heritage, food security and provides livelihoods to the rural communities. TRVs also have economic importance due to growing demand for indigenous varieties in urban areas, desi varieties can be exported, capitalizing on global demand and conservation desi varieties can lead to value addition through processing and branding. Over the past thirty years, the Green Revolution has led to a significant increase in rice yields; however, this surge in food production has not eradicated poverty and hunger. In fact, rice yields have remained stagnant during this period, despite the availability of improved varieties and technologies. Globally, at least two billion individuals go to bed hungry each night, with a staggering 320 million of those in India alone. The introduction of high-yielding varieties (HYVs) has resulted in the near extinction of many traditional varieties (TRVs) in farmers' fields. Although production costs have risen, aromatic rice varieties such as Gobindobhog, Badsabhog, Radhatilak, Kalonunia, and Tulaipanji, along with fine rice types like Dudheswar and Seetasail, continue to command good market prices. The chemical-intensive practices of the Green Revolution have not only diminished local crop genetic diversity but have also eradicated their wild relatives, which are vital sources of unique genes for disease and pest resistance. Initially, farmers were attracted by the high yields of these so-called "miracle" seeds, overlooking the associated costs of external inputs, the subsequent loss of non-grain biomass, the decline www.extensionjournal.com of desirable traits (such as resistance to diseases, pests, drought, and flooding), and the significant environmental degradation affecting soil and water quality. Over time, the average grain yield of the widely used modern variety (HYV) MTU-7029 in West Bengal has decreased from 5 t ha-1 to approximately 3.75 t ha-1 in many farmers' fields. These HYVs do not provide a significant yield advantage in marginal lands, such as drought-prone areas, saline soils, or deep-water conditions. A survey conducted by the World Wildlife Fund (WWF) in India in 1994 across six districts of southern West Bengal identified 137 traditional rice varieties still thriving in marginal farming conditions. An examination of the factors contributing to the persistence of these varieties revealed several key points: Small and marginal farmers cultivating traditional rice varieties (TRVs) often lacked the financial means to purchase expensive inputs required for highyielding varieties (HYVs). Additionally, HYVs were unsuitable for cultivation in dry uplands and wet lowlands, where only a select few locally adapted varieties could thrive. Many indigenous varieties were favored for their unique aroma and flavor, which were notably absent in HYVs. Furthermore, certain native varieties commanded higher market prices compared to HYVs. Numerous varieties exhibited resilience to drought and flooding, as well as adaptability to poorly drained and lowland environments. A significant number of these varieties also demonstrated resistance to diseases and pests. Some possessed exceptional traits, such as tolerance to salinity and alkalinity, and the ability to grow in deep-water inland areas. In light of this, a study was conducted to assess the performance of selected traditional rice varieties in comparison to widely used HYVs, alongside a genetic analysis.

A study was undertaken to evaluate the performance of traditional rice varieties compared to popular high-yielding varieties, along with genetic analysis. The objectives included: 1. Identifying existing landraces of rice in the Godavari zone. Data collection tools: Semi structured interview schedule was used to collect primary data from farmers. And missing data was obtained through secondary sources.

Statistics Used: Frequency, Percentage and Ranking.

Results & Discussion

A total of 28 desi rice varieties were collected from the farmers and analyzed through image processing technique. Rice seeds are counted and categorized according to their length, width, and length-to-breadth ratio. The lengthbreadth ratio is determined as L/B = [((Average length of rice grain)/(Average breadth of rice)] where length is the average length of rice grain and width is the average breadth of rice grain. Based on the kernal size and form 28 varieties were categorized in to five categories and presented in the Table 1. This variety is rich in ca, Fe and zinc. Highly nutritious and abundant in fiber, contributing to the alleviation of joint pain. [3] , Muralikrishnan (2021) [4] and Rubilah et al (2023) [5] . It could be inferred from the Table 4.0 that, a total of 3 land races falls under short slender kernel type category with less than 6.0 mm kernel length and more than 3.0 mm L/B ratio. The bio diversity of land races includes, the duration is ranging from 110 -130 days. The kernel characteristics includes the colour of kernel is white. The kernel length is from 5.32 to 5.38 mm, kernel breadth from 1.49 -1.68 mm and the L/B ratio is ranging from 3.17 - [6] .

It could be inferred from the Table 5.0 that, a total of 13 land races falls under short bold kernel type category with less than 6.0 mm kernel length and less than 2.5 mm L/B ratio. The diversity of theses land races includes, the duration is ranging from 110 -150 days. The kernel characteristics includes the colour of kernel is ranging from red, white and black. The kernel length is from 3.66 to 5.67 mm, kernel breadth from 1.90 -2.80 mm and the L/B ratio is ranging from 1.46 -2.35. The panicle diversity includes panicle length is ranging from 19.5 -29.5 cm, number of grains per panicle is ranging from 42 to 361 and the test weight of the varieties is ranging from 11.3 -27.6 gm. These landraces exhibit diverse characteristics, highlighting their potential for conservation and utilization in rice breeding programs.

The results are somewhat inline with the results of Bera (2020) [1] and Shanmugam et al. (2023) [6] . (2020) [2] .

Conclusion

The study indicating that, the conservation and promotion of rice landraces in the Godavari zone are crucial for food www.extensionjournal.com

References

1. Bera A. Indigenous rice of West Bengal. Agric Food ENewslet. 2020;2(1):648-650.
2. Blakeney M, Krishnankutty J, Rajesh KR, Siddique KHM. Agricultural innovation and the protection of traditional rice varieties: Kerala a case study. Front Sustain Food Syst. 2020;3(1):1-11.
3. Manickam S, Suganthy M, Sunitha R, Jansirani R, Krishnan R, Ganesh R, et al. Evaluation of traditional varieties of rice (Oryza sativa L.) for yield under organic production system. Indian J Agric Res. 2024;58(6):1187-1192.
4. Muralikrishnan L, Rabindra NP, Dass A, Anil KC, Bharat K, Shadi ST, et al. Elucidating traditional rice varieties for consilient biotic and abiotic stress management under changing climate with landscapelevel rice biodiversity. Land. 2021;10(1058):1-17.
5. Shanmugam A, Manivelan K, Deepika K, Nithishkumar G, Blessy V, Monihasri RB, et al. Unravelling the genetic potential of native rice (Oryza sativa L.) landraces for tolerance to early-stage submergence. Front Plant Sci. 2023;14(1):1-17.