Booting stage is defined as swelling of the flag leaf sheath (late panicle initiation stage). It is the most critical stage for water requirement in rice.

Hybrid rice was first developed by China in the late 1970s using the cytoplasmic male sterility (CMS)–fertility restorer gene system.

Durum wheat (tetraploid, 2n=28) is mainly used for semolina products like suji and semya and occupies about 12% of wheat area in India.

Norin-10 dwarfness resulted from two recessive genes, Sd1 and Sd2. These genes were crucial in developing semi-dwarf, high-yielding wheat varieties.

RAJ-4120 (2009) is specifically mentioned as resistant to the UG-99 race of rust and has a yield potential of 48–58 q/ha, making it an important disease-resistant variety.

In submerged paddy fields, nitrate nitrogen is easily lost through leaching and denitrification, reducing nitrogen use efficiency

Wheat is predominantly a self-pollinated crop due to cleistogamous flowers. Natural cross-pollination is very low (generally <1%).

IR-8 was developed from a cross between Peta and Dee-gee-woo-gen and released in 1966 by IRRI. It was the first photo-insensitive high-yielding dwarf variety.

Perling Index is used to determine grain hardness. A higher P.I. value means the grain is softer (lower kernel hardness), an important quality parameter.

As per the given data, hybrid rice requires only 15 kg/ha seed rate, which is much lower than broadcasting (100 kg/ha) and drilling (60 kg/ha).

Common bread wheat belongs to Triticum aestivum. It is the most widely cultivated wheat species and responsible for the Green Revolution in India.

Rice grows best in clay and clay loam soils. It prefers acidic soils with an optimum pH range of 4–6, as mentioned in the text.

Silicon deficiency is corrected by applying basic slag @ 1.5–2.0 t/ha, which is a common source of calcium silicate.

Although depth varies with dwarfing genes, an average depth of 5 cm is considered ideal for proper germination and coleoptile emergence.

Wheat follows the C₃ photosynthetic pathway and is a long-day plant, requiring longer photoperiods for flowering.

Oryza sativa is a diploid species with chromosome number 2n = 24. It is the principal cultivated rice species worldwide.

With SRI, average yields of 6–7 tons/ha are reported, compared to 2–3 tons/ha under conventional methods, along with seed and water savings.

The upper 1–10 mm layer of waterlogged soil contains oxygen and is termed the “oxidized zone.” Below it lies the oxygen-deficient “reduced zone.”

Resistance to isoproturon in Phalaris minor has been reported. Sulfosulfuron (20 g/ha) or metasulfuron can be used as alternative control measures.

Common bread wheat (T. aestivum) is hexaploid (2n=42) and occupies nearly 87% of India’s wheat area. It is mainly used for chapati and bakery products.

The text states that puddling increases soil bulk density from about 1.4 to 1.7 g/cc due to destruction of soil aggregates.

Golden Rice contains beta-carotene gene inserted through genetic engineering, which enhances Vitamin A content in rice grains.

The main protein in rice is Oryzenin. It is the dominant storage protein found in rice grain.

Norin-10, a Japanese variety, carried dwarfing genes used by Dr. Borlaug. It played a key role in developing high-yielding dwarf wheat varieties.

Beushening involves cross ploughing of the young crop 4–6 weeks after sowing in 5–10 cm standing water to control weeds, optimize crop stand, and improve soil aeration.

2,4-D is a selective herbicide for dicot weeds in wheat. Its spray drift can damage sensitive broadleaf crops like pulses grown nearby.

Echinochloa crusgalli (barnyard grass) and E. colona are major weeds in rice. Weed problems are generally less in lowland transplanted rice compared to upland direct-seeded rice.

The primary objective of puddling is to reduce percolation losses of water. It also helps in weed control and increasing nutrient availability.

In flooded rice fields, anaerobic conditions promote denitrification, converting nitrates into gaseous forms (N₂, N₂O), leading to major nitrogen loss.

CRI is the most critical stage for irrigation in wheat. Adequate moisture at this stage ensures proper crown root development and determines final yield.

Iron deficiency in rice causes chlorosis and the characteristic “white eye” symptom, especially in poorly drained or calcareous soils.

Rice produces a branched inflorescence called a panicle. This is a key botanical feature frequently asked in agriculture and botany exams.

Propanil (Stam F-34) @ 3 kg a.i./ha is applied about 1 week after transplanting as a post-emergence herbicide in rice.

Jaya, evolved by Dr. Shastry in 1968 from TN-1 × Type 141, showed higher yield than TN-1 and IR-8 and was called “Miracle rice in India.”

DBW-17 (2006) is mentioned as suitable for bread making, highlighting its grain quality characteristics preferred for bakery products.

Azolla forms a symbiotic association with the blue-green alga Anabaena azollae, contributing significantly to biological nitrogen fixation in paddy fields.

As per the page, productivity ranking is USA > Japan > China. Hence, USA has the highest rice productivity among the listed countries.

Booting stage is highly sensitive to water stress. Moisture deficiency at this stage significantly reduces yield due to poor panicle development.

CRI is the first and most critical irrigation stage in wheat. Adequate moisture at this stage ensures proper root development and higher yield potential.

Boro is the spring rice crop, sown in November–December. Aus is sown in April–May, while Aman (Kharif) is sown in June–July.

Kalyan Sona is a double-gene dwarf variety developed from Kalyan 227 × Sona 227. It was one of the important Green Revolution wheat varieties in India.

2,4-D (500 ml/ha) is applied as post-emergence at 30–35 days after sowing. Early application may cause ear malformation in wheat.

Drilling with seed-cum-fertilizer drill ensures uniform placement of seed and fertilizer, better germination, and efficient nutrient use.

Khaira disease in rice is caused by zinc (Zn) deficiency, usually observed at the nursery stage. It leads to yellowing and stunted growth of plants.

The recommended dose is 120 kg N, 60 kg P₂O₅, and 40 kg K₂O per hectare. Half N is basal and remaining half is applied at first irrigation.

Iron toxicity in rice is known as “browning of rice.” It is common in waterlogged acid sulphate soils and initially shows purple coloration at leaf tips.

Phalaris minor (little seed canary grass) is the most serious grassy weed in wheat, especially in the rice–wheat cropping system.

The variety Phalguna is specifically mentioned as tolerant to iron toxicity, making it suitable for affected soils.

The recommended NPK ratio mentioned is 100:60:60 along with 25 kg zinc sulphate at last puddling for high-yielding varieties.

Booting is the reproductive stage marked by swelling of the uppermost internode. The spike remains enclosed within the flag leaf sheath.

Cool temperature (15–20°C) during grain filling ensures proper starch accumulation. High temperature causes forced maturity and shriveled grains.

FIRB is a modern sowing method involving furrow irrigated raised beds. It provides higher yield compared to conventional methods.

Indica rice is characterized by tall stature, weak stem, elongate grains, and low responsiveness to high input conditions. It is mainly grown in tropical and subtropical regions.

TKM-6 is specifically mentioned as tolerant to BLB (Bacterial Leaf Blight). IR-8 and Lunishree are noted for salinity tolerance, while PRH-10 is the first basmati hybrid.

After China, India commercialized hybrid rice varieties such as APRH-1, APRH-2, KRH, and MGR-1.

Half dose of nitrogen is applied as basal, and the remaining half is top dressed at first irrigation for efficient uptake and better growth.

In the Dapog (mat-type) nursery method, seedlings are ready for transplanting within 11–14 days, making it a quick and space-efficient technique.

For normal line sowing under irrigated conditions, 100 kg seed per hectare is recommended. Late sowing or broadcasting requires higher seed rate (125 kg/ha).

Although 400–500 liters are required for producing 1 kg of dry matter, rice requires about 5000 liters of water to produce 1 kg of rice grain, making it a highly water-intensive crop.

SRI was developed by Henri de Laulanie in Madagascar in the 1980s as an agro-ecological method to increase rice productivity