SML 668 Moong Seed — Sowing & Yield Guide

Quick facts

Crop: Moong (Green Gram)
Type: Open-pollinated
Season: Zaid / summer
Maturity period: 60–65 days
Seed rate: 15 kg of seed an acre for SML 668, against 12 kg an acre for other summer moong varieties (PAU)
Expected yield: 8–10 q/ha
Suitable soil: Loam
Disease resistance: Yellow mosaic virus resistant
Release: Widely reported release around 2008 by PAU, Ludhiana — not independently confirmed via a primary document

Actual yield depends on sowing time, soil, irrigation, weather, seed quality and crop management.

About this variety

SML 668 is an early-duration, dwarf mungbean (green gram) variety bred by Punjab Agricultural University (PAU), Ludhiana. Multiple independent seed-trade and extension listings consistently describe it maturing in about 60–65 days on a compact plant with long pods carrying 10–11 seeds each, resistant to yellow mosaic virus and tolerant of powdery mildew and sucking pests (jassid, whitefly, thrips). Seed-trade listings give its release year as around 2008, but no PAU or ICAR release document confirms it, so treat the year as approximate. No parentage is given here for the same reason.

Should you pick this variety?

Choose SML 668 when the time between wheat and the next crop is the whole problem. It takes 60–65 days on a dwarf, compact plant, and it is resistant to yellow mosaic and tolerates powdery mildew, jassid, whitefly and thrips. The states listed for it are Punjab, Haryana and Uttar Pradesh. The price you pay is yield: 8–10 q/ha is the lowest figure among the moong varieties here. Choose Pusa Vishal or IPM 410-3 (Shikha) instead if your gap is long enough and you would rather have 10–16 q/ha. Choose IPM 205-7 (Virat) if the gap is even shorter.

Sowing & cultivation

Sowing time20 March to 10 April for summer moong in Punjab, and it can go on to the third week of April, though there is then a risk of pre-monsoon showers when the crop matures (PAU)
Seed rate15 kg of seed an acre for SML 668, against 12 kg an acre for other summer moong varieties (PAU)
SpacingRows 17.5 to 22.5 cm apart, with the seed 4 to 6 cm deep
Fertilizer5 kg N (11 kg urea) and 16 kg P2O5 (100 kg single superphosphate) an acre at sowing, for a crop sown after wheat. A crop sown after potato needs no fertiliser (PAU)

Full Moong (Green Gram) growing guideSowing time, nutrients, irrigation, pests, costs and prices for Moong (Green Gram) as a whole crop. This is the advice that holds for every variety.

Advantages & considerations

Why farmers may choose it

Short 60–65 day duration and a dwarf, compact plant habit make it a reliable catch crop between wheat harvest and the next kharif sowing, without delaying either.
Yellow mosaic virus resistance plus tolerance to powdery mildew, jassid and whitefly reduces spray needs relative to older, more disease-prone moong lines.

Things to consider

No PAU or ICAR release document confirms the exact release year or the parentage. The ~2008 date comes from seed-trade listings that repeat each other, so treat it as approximate.

Suitable regions

States this variety is recommended for — check locally, since a state can have more than one recommended zone.

Punjab
Haryana
Uttar Pradesh

Counting back from the next sowing date

SML 668 works only if you count from the far end. Write down the date your next crop must go in. Subtract 65 days. That is the last day you can sow SML 668. If you sow later, it will still be standing when you need the field.

Then look at the date your wheat comes off. If wheat harvest and that last sowing date are only a few days apart, there is no time to prepare the field, and a rushed moong crop gives little.

In a good gap, 8–10 q/ha is extra grain and a legume in the rotation before the next crop. In a poor gap it is a cost with no return. Decide with the dates, not with hope.

Can you keep your own planting material?

This is an open-pollinated variety, so seed from a healthy crop of your own can be sown again. Keep seed only from disease-free plants, dry it properly, store it cool and dry, and bring in fresh certified seed every three to four years so the variety does not drift.

How it compares with other varieties

Every Moong (Green Gram) variety with a page on this site, side by side. The row for this page is highlighted.

Variety	Best for	Maturity	Yield	States
IPM 02-3	A well-tested north-west moong for kharif or summer, with strong yellow mosaic resistance	65–70 days	12–15 q/ha	Punjab, Haryana, Rajasthan, Uttar Pradesh
IPM 205-7 (Virat)	The fastest moong on this list, about 55 days, with three disease resistances	52–56 days	13–15 q/ha	Karnataka, Tamil Nadu, Madhya Pradesh, Gujarat, Rajasthan, Maharashtra, Uttar Pradesh
IPM 410-3 (Shikha)	High published yield and pods that ripen together, so fewer pickings and a smaller labour bill	60–65 days	13–16 q/ha	Punjab, Haryana, Madhya Pradesh
Pusa Vishal	Very bold, shiny moong grain that earns a better market grade, for summer sowing in the north-west	60–65 days	10–12 q/ha	Rajasthan, Madhya Pradesh, Uttar Pradesh
Samrat (PDM 139)	Early kharif moong for eastern Uttar Pradesh and Bihar, where yellow mosaic is the worry	60–65 days	10–12 q/ha	Uttar Pradesh, Bihar
SML 668this page	A short, dwarf moong for the gap between wheat harvest and the next kharif sowing	60–65 days	8–10 q/ha	Punjab, Haryana, Uttar Pradesh

Other Moong (Green Gram) varieties in the finder, for comparison.

Tools for this crop

The numbers you need next: how much seed to buy, whether the lot germinates, what the fertilizer bill looks like and what Moong (Green Gram) is selling for.

Subsidy and government support

Schemes that help with the cost of Moong (Green Gram) seed or planting material. Rules and the application route are on each scheme page.

Frequently asked questions

Is SML 668's release year officially confirmed?

Not from an official release record. Seed-trade and extension listings consistently cite around 2008, but no PAU or ICAR document confirms it, so treat the year as indicative rather than official.

What makes SML 668 useful in a wheat-based rotation?

Its 60–65 day duration lets it be sown as a short-window catch crop between the wheat harvest and the next kharif sowing — too short to delay either main crop, which is why PAU markets it specifically for that gap.

How much yield should I expect from SML 668?

The figure above is 8–10 q/ha, lower than Pusa Vishal (10–12) and IPM 410-3 (13–16). You are paying for the short, compact crop, not for yield.

Does SML 668 need a lot of spraying?

Less than older, disease-prone moong. It is resistant to yellow mosaic and tolerant of powdery mildew, jassid, whitefly and thrips. Still look at the field every few days, because tolerant does not mean untouched.

How long are the pods of SML 668 and how many seeds do they carry?

Seed-trade and extension listings describe long pods with 10–11 seeds each, on a dwarf plant.

SML 668 or Virat for the gap after wheat?

If the gap is very short, Virat: about 55 days against 60–65 days for SML 668, with 13–15 q/ha listed by ICAR-IIPR against 8–10 q/ha. SML 668 earns its place when the gap fits 60–65 days and you want a dwarf plant that tolerates powdery mildew, jassid, whitefly and thrips, which can mean fewer sprays.

Can I keep seed from SML 668 for the next season?

Yes. SML 668 is an open-pollinated variety from PAU Ludhiana, so saved seed grows true to type. Take seed from healthy plants, dry the pods fully and store the seed dry. The exact release year is not confirmed in any PAU or ICAR document, so ask for the variety name on the bag when you buy fresh seed.