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

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

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

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

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

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.

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.”

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

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

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

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

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

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

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.

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.

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.

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

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

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.

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

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.

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

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

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.

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.

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

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.

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

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

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.

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

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

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

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

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

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

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

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.

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).

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.

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

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

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.

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

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

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

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.

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

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.

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

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

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

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

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

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.

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

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

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.”