What are the pitfalls to watch out for when introducing rice varieties?

Rice has entered the sowing season. In recent years, farmers introducing varieties on their own initiative has become fairly common, but few of the introduced varieties perform well in overall traits, and some have even caused severe yield reductions. In fact, the seeds farmers need can be purchased from their local agriculture department and seed department. If introduction is truly necessary, be careful to avoid the following pitfalls.

1. Blindly introducing large-panicle varieties. Many farmers blindly introduce varieties for their large panicles, extra-large panicles, or wolf-tail rice, believing that a large panicle means high yield, but the result is the opposite of what they wanted. Some varieties do indeed have large panicles, even extra-large ones, but their drawbacks are very obvious. For example, low seed-setting rate, seriously insufficient effective panicles, easy lodging, susceptibility to disease, and poor grain quality. Despite the large panicle type, the yield is not high. Besides the number of grains per panicle (number of spikelets), the factors that make up yield also include the seed-setting rate, the number of effective panicles, and grain weight. Therefore, to determine whether a variety is good or bad, you must look not only at the size of the panicle but also at its other traits. Only varieties with high yield, good grain quality, strong resistance, and a moderate growth period are worth promoting in production.

2. Introducing varieties without trial planting. Many introducers believe that a good variety from another region will certainly perform well once brought to their own area, and so they plant it blindly without trial planting, resulting in yield reductions. Some good varieties do indeed perform well locally, but they may not necessarily perform well when introduced and planted elsewhere; some varieties have a longer growth period after introduction, so you must pay attention to whether they can safely reach full heading; some varieties have a shorter growth period after introduction, so you must guard against the possibility of yield reduction. Rice is a short-day plant. Among these, the early indica type is strongly sensitive to temperature, while the late indica type is not only strongly sensitive to temperature but also strongly sensitive to photoperiod. When southern varieties are introduced to the north, or low-altitude varieties are introduced to high-altitude areas for planting, the growth period lengthens, and for late rice you must also consider whether it can safely reach full heading, so generally varieties with a shorter growth period should be introduced. When northern varieties are introduced to the south, or high-altitude varieties are introduced to low-altitude areas for planting, the growth period shortens, so generally varieties with a longer growth period should be introduced. After introduction, small-area trial planting must be carried out. Only after 1-3 years of successful trial planting, confirming good performance in overall traits such as disease resistance and high yield, can it be planted on a large scale.

3. Introducing varieties without quarantine. Some rice pests, diseases, and weeds are quarantine objects, but they are confined only to epidemic areas. However, some introducers have no awareness of quarantine and introduce varieties casually. Without quarantine, once some quarantine objects spread along with the introduced varieties, the harm is endless and the losses are immeasurable. Therefore, no matter how few or how many varieties are introduced, they must be quarantined by the quarantine agency of the local agriculture department. If there are quarantine objects, resolutely do not introduce them; if there truly are no quarantine objects, obtain a quarantine certificate when introducing them.

4. Introducing varieties that have not been approved. Some introducers casually propagate the introduced varieties and carry out business activities with them, and when farmers buy seeds they often do not consider whether the variety has passed national or provincial or municipal approval. In the seed cases investigated and handled in recent years, farmers all suffered losses because they casually bought varieties that had not been approved (or had failed approval). Even for varieties that have passed approval (or recognition), you must also pay attention to altitude adaptation, disease resistance, and so on. Rice farmers should take this as a warning and introduce varieties cautiously.