Which among the followings is not the characteristic of the... | Agrigyan

• Wrapper Tobacco (Option 3): Cigar wrapper tobacco leaves must be ultra-thin, silky, elastic, light in color, and mild with low nicotine content. Topping stimulates secondary leaf thickening and nicotine synthesis, so wrapper tobacco plants are left untopped (or topped very late/high) and de-suckering is avoided to keep leaves fine and tender.
• Chewing Tobacco (Option 1): Requires thick, coarse, leathery, dark leaves with high nicotine and gums; severe low topping and rigorous de-suckering are mandatory.
• Cigar Filler & Binder (Option 2): Topped to promote moderate body and nicotine development.
• Bidi Tobacco (Option 4): Topped strictly at 12–14 leaves followed by repeated de-suckering to maximize leaf thickness, spangle development, and high nicotine. (Correct answer: Option 3)

• Electrical Resistance Blocks (Gypsum Blocks): Measure soil moisture tension by calibrating electrical resistance across embedded concentric wire electrodes inside a porous calcium sulfate block against soil water potential.
• Operational Range: Gypsum blocks function effectively in intermediate to dry soils ranging from -0.5 to -15 bars (-0.5 to -50 bars).
• Limitation: In very wet soils (0 to -0.3 bars), gypsum blocks are insensitive because the pore water within the block remains saturated, whereas tensiometers operate best in the wet range (0 to -0.85 bars). (Correct answer: Option 3)

• Step 1: Calculate Total Hills per Hectare:

$$\text{Area} = 10,000\text{ m}^2, \quad \text{Spacing} = 0.20\text{ m} \times 0.20\text{ m} = 0.04\text{ m}^2$$ $$\text{Total Hills} = \frac{10,000}{0.04} = 250,000\text{ hills/ha}$$

• Step 2: Seedlings Required for Planting:

$$\text{Seedlings needed in main field} = 250,000 \times 2 = 500,000\text{ seedlings}$$

• Step 3: Account for 20% Uprooting Damage:

$$\text{Total seedlings required in nursery} = \frac{500,000}{1 - 0.20} = \frac{500,000}{0.80} = 625,000\text{ seedlings}$$

• Step 4: Account for Germination (90%) and Purity (90%):

$$\text{Real Value of Seed} = 0.90 \times 0.90 = 0.81$$ $$\text{Total seeds to be sown} = \frac{625,000}{0.81} \approx 771,605\text{ seeds}$$

• Step 5: Calculate Seed Rate using Test Weight (25 g per 1000 seeds):

$$\text{Seed Rate (kg/ha)} = \frac{771,605 \times 25\text{ g}}{1000 \times 1000} = 19.29\text{ kg/ha} \approx 19.3\text{ kg/ha}$$

• Conclusion: The required seed rate is 19.3 kg/ha. (Correct answer: Option 4)

• Variance Definition: In agricultural statistics and biometrics, variance (denoted by $\sigma^2$ for population or $s^2$ for sample) is the mean of the squared deviations of individual observations from their arithmetic mean.
• Relationship with Standard Deviation: Standard deviation is the positive square root of variance ($\text{SD} = \sqrt{\text{Variance}}$), which means variance is mathematically the square of the standard deviation ($\text{Variance} = \text{SD}^2$). (Correct answer: Option 2)