Weed management in direct-seeded rice

Abstract

Rice (Oryza sativa), the staple food of more than half of the population of the world, is an important target to provide food security and livelihoods for millions. Direct seeding of rice (DSR) refers to the process of establishing the crop from seeds sown in the field rather than by transplanting seedling from the nursery. Before the advent of Green revolution and adoption of irrigation, rainfed rice was often broadcasted into moist soil and yields were low, variable and highly prone to weed competition. Weed spectrum and degree of infestation in rice field are often determined by rice ecosystems and establishment methods. Research evidences at different places has shown around 20-100% losses due to weeds such as Echinochloa spp., Leptochloa spp., Cyanotis spp., Commelina sp., Digitaria spp. and Alternanthera sp in DSR. Integrated weed management approach based on the critical period of crop weed competition, involving different direct and indirect control measures, has been developed and widely adopted by farmers to overcome weed problem in DSR in a sustainable way. Stale seed bed combined with herbicide (paraquat/glyphosate) and zero till results in better control. About 53% lower density was recorded due to stale seed bed. Brown manuring of Sesbania reduces weed population by 50%. Mulches, crop rotation and rice cultivars like 'Narender 359' and 'Sarjoo 52' were found better for Indo-Gangetic plains. Application of penoxsulam 25 g/ha as broad-spectrum, azimsulfuron + metsulfuron-methyl for Cyperus spp., pendimethalin at 1.25 kg/ha for Echinochloa spp. were found suitable for chemical weed management.Weed-competitive and allelopathic rice varieties, seed priming for increased weed competitiveness, higher seeding density should be considered as a management strategy.

Bio-efficacy of herbicides in direct-seeded rice

“…Significantly maximum number of weeds was found under unweeded check. These results are in agreement with those reported by Singh et al (2016).…”

Herbicide options for effective weed management in dry direct-seeded rice under scented rice-wheat rotation of western Indo-Gangetic Plains

“…Moreover, seedlings of some grassy weeds such as Echinochloa crus-galli (L.) look similar to rice seedlings ( Rao and Moody, 1987 , Rao and Moody, 1988 ), making hand weeding more tedious, difficult, and less effective. However, adoption of DSR technology usually leads to shift in weed flora composition towards difficult-to-control weeds ( Singh et al., 2013 ). In this situation, use of herbicides is becoming more popular in DSR because they are more effective, easy to apply, provide selective control, saves on labour and costs less.…”

Dinamika Populasi Gulma Akibat Aplikasi Herbisida Metil Metsulfuron pada Padi Sawah Sistem Tanam Pindah (Tapin) dan Tanam Benih Langsung (Tabela)

“…Kata kunci: Pergeseran gulma, Metil-metsulfuron, Tapin, Tabela PENDAHULUAN Keberadaan gulma merupakan salah satu masalah yang dapat mengakibatkan kehilangan hasil pada padi sawah. Besarnya kehilangan hasil salah satunya ditentukan oleh cara budidaya tanaman itu sendiri (Singh et al, 2016). Budidaya tanaman padi sawah dapat dilakukan dengan cara Tanam Pindah (Tapin) dan Tanam Benih Langsung (Tabela).…”

“…Tumbuhan yang terkena herbisida metil metsulfuron umumnya memperlihatkan gejala klorosis dan nekrosis pada 2 minggu setelah aplikasi dan pada akhirnya mati (Marble et al, 2016 ;Raj & Syriac, 2017) Penggunaan sistem budidaya dan herbisida yang berbeda mengakibatkan terjadinya pergeseran jenis dan komposisi gulma ke arah yang berbeda. Perubahan sistem tanam Tapin menjadi Tabela mengakibatkan gulma bergeser menjadi jenis rumput atau teki yang lebih berbahaya dan sulit untuk dikendalikan (Kumar & Ladha, 2011;Singh et al, 2016). Hal ini dapat terjadi akibat jumlah air yang digunakan pada awal pertanaman sistem Tabela yang lebih sedikit, sehingga gulma rumput dan teki tumbuh lebih baik dibandingkan gulma daun lebar (Singh et al, 2016 .…”

“…Perubahan sistem tanam Tapin menjadi Tabela mengakibatkan gulma bergeser menjadi jenis rumput atau teki yang lebih berbahaya dan sulit untuk dikendalikan (Kumar & Ladha, 2011;Singh et al, 2016). Hal ini dapat terjadi akibat jumlah air yang digunakan pada awal pertanaman sistem Tabela yang lebih sedikit, sehingga gulma rumput dan teki tumbuh lebih baik dibandingkan gulma daun lebar (Singh et al, 2016 . Faktor pertama adalah sistem tanam padi, yang terdiri atas Sistem Tapin (T1) dan Tabela (T2).…”