Agri Quiz: Agronomy: Rice MCQ

Correct Answer: Oryzenin
The primary protein found in rice is called Oryzenin. Rice generally has a lower protein content (6-7%) compared to other major cereals.

Correct Answer: Dee-Gee-Woo-Gen
The gene responsible for the dwarf characteristic in many rice varieties is 'Dee-Gee-Woo-Gen'. This gene was crucial in developing high-yielding, lodging-resistant rice cultivars.

Correct Answer: 26.5-29.5°C
The ideal temperature for the blooming or flowering stage in rice cultivation is between 26.5°C and 29.5°C. Temperatures outside this range can affect pollination and grain setting.

Correct Answer: Tea and Potato
Slightly acidic soil conditions, with a pH range of 4.5 to 6, are considered suitable not only for rice but also for tea and potato cultivation.

Correct Answer: 5-8 kg/ha
The System of Rice Intensification (SRI) method requires a significantly lower seed rate compared to traditional methods, typically ranging from 5 to 8 kg per hectare.

Correct Answer: Booting and Panicle Initiation
The critical stages where water availability is most crucial for rice yield are the Booting stage and the Panicle Initiation stage. Water stress during these periods significantly reduces grain formation.

Correct Answer: 66-67%
Hulling percentage, the ratio of white rice obtained from paddy, is typically around 66-67%, meaning about two-thirds of the paddy weight is retained as white rice after husk removal.

Correct Answer: Vitamin B complex (especially B1)
The milling process, which removes the bran and germ layers to produce polished white rice, leads to a significant loss of B vitamins, particularly Thiamine (Vitamin B1).

Correct Answer: To harden grains and retain nutrients like B12
Parboiling involves steam treating paddy before milling. This process helps retain some nutrients, like Vitamin B12, within the grain and makes the grains harder.

Correct Answer: Parenchyma (Aerenchyma)
Rice plants possess Parenchyma tissue (specifically Aerenchyma) in their leaves and stems. This tissue contains air spaces that allow for efficient oxygen transport from the leaves down to the submerged roots.

Correct Answer: Azotobacter
While Azolla and BGA are common biofertilizers for flooded rice fields, Azotobacter is mentioned as being suitable for use in paddy fields where water is not standing. It fixes atmospheric nitrogen.

Correct Answer: Timely sowing and saving water
The Drum Culture Technique, developed by Dr. Dastane and IRRI, aims to facilitate timely sowing of rice and conserve water, often utilizing pre-germinated seeds.

Correct Answer: Both Ammonium (NH4+) and Nitrate (NO3-)
Rice plants are capable of absorbing nitrogen in both the ammonium (NH4+) and nitrate (NO3-) forms. However, in flooded anaerobic conditions, the ammonium form is often more prevalent and preferred.

Correct Answer: 5000 liters
Rice is a water-intensive crop, requiring approximately 5000 liters of water to produce just 1 kg of dry paddy. This highlights the crop's high water demand.

Correct Answer: Methane (CH4)
Flooded rice paddies create anaerobic conditions suitable for methanogenic bacteria, leading to the emission of Methane (CH4), a potent greenhouse gas.

Correct Answer: Beriberi
Beriberi is a disease caused by Thiamine (Vitamin B1) deficiency. Continuous consumption of highly polished rice, which has lost most of its thiamine during milling, can lead to this condition.

Correct Answer: Los Baños-Philippines
The International Rice Research Institute (IRRI), a major center for rice research and development, is located in Los Baños, near Manila, in the Philippines.

Correct Answer: Mimicry weed
Echinochloa colonum, commonly known as jungle rice or barnyard grass, is a major mimicry weed in rice fields. It closely resembles rice seedlings, making it difficult to distinguish and control early on.

Correct Answer: Benthiocarb
Benthiocarb, marketed under the trade name Saturn, is specifically as a herbicide used for weed control in rice, particularly its use in Rajasthan.

Correct Answer: 1/10th
For the Wet Bed Method, the nursery area is generally prepared on 1/10th of the total area that is intended for transplanting in the main field.

Correct Answer: 11-13 days
The Dapog method is known for producing transplantable seedlings very quickly, typically within 11-13 days after sowing. This is much faster than traditional wet or dry bed methods.

Correct Answer: Dapog Method
The Dapog method requires the smallest nursery area, needing only about 25-30 square meters to raise seedlings for one hectare of main field.

Correct Answer: Madagascar
The System of Rice Intensification (SRI) was developed in Madagascar in the 1980s by Fr. J. Henri de Laulanié.

Correct Answer: Javanica
Oryza sativa subsp. Javanica is mainly cultivated in Indonesia and is also referred to as 'Balu Paddy'. It is resistant to lodging.

Correct Answer: Aman
Based on the sowing season, rice grown during the main monsoon/winter period (sown June-July, harvested Nov-Dec) is traditionally called 'Aman' rice.

Correct Answer: Vitamin A
Golden Rice is genetically modified to produce beta-carotene, a precursor to Vitamin A. It was developed by Ingo Potrykus and team to help address Vitamin A deficiency, particularly in regions heavily reliant on rice.

Correct Answer: G.S. Khush
Dr. Gurdev Singh Khush (G.S. Khush) from IRRI is credited with developing the concept of 'Super Rice', aiming for varieties with significantly higher yield potential and nutritional value.

Correct Answer: IR-8
IR-8, developed at IRRI, is often called the 'Miracle Rice' or 'Magic Rice of the World' due to its high yield potential which played a significant role in the Green Revolution.

Correct Answer: TN-1 (Taichung Native-1)
TN-1 (Taichung Native-1) was the first semi-dwarf rice variety developed and released, incorporating the Dee-Gee-Woo-Gen for reduced height. It originated from Taiwan.

Correct Answer: Basmati Rice
The Yellow Stem Borer is noted to cause the most significant damage specifically to Basmati rice varieties. Its infestation leads to characteristic 'white ears'.

Correct Answer: Grassy Stunt Virus
The Brown Planthopper (BPH), Nilaparvata lugens, is a major sucking pest of rice and acts as a vector for the Grassy Stunt Virus disease.

Correct Answer: Brown Leaf Spot
The great Bengal famine in 1943 was significantly exacerbated by a severe epidemic of Brown Leaf Spot disease, caused by the fungus Helminthosporium oryzae, which destroyed the rice crop.

Correct Answer: Bacterial Leaf Blight (BLB)
Kresek refers to the acute, systemic wilting phase of Bacterial Leaf Blight (BLB), caused by Xanthomonas oryzae pv. oryzae. It often affects seedlings in the nursery, causing rapid drying and death.

Correct Answer: Zinc (Zn)
Khaira disease is a physiological disorder in rice caused by Zinc (Zn) deficiency, particularly common in submerged or alkaline soils. It was first identified by Dr. Y.L. Nene.