Poor RNA recovery could be due to one or more of the following:

• Column has become clogged.

  Do not exceed the recommended amounts of starting materials. The amount of starting material may need to be decreased if the column shows clogging below the recommended levels. See also “Clogged Column”.

• An alternative Elution Solution was used.

  It is recommended that the Elution Solution A supplied with this kit be used for maximum RNA recovery.

• Ethanol was not added to the lysate.

  Ensure that the appropriate amount of ethanol is added to the lysate before binding to the column.

• Ethanol was not added to the Wash Solution A.

  Ensure that the indicated amount of 96 - 100% ethanol is added to the supplied Wash Solution A prior to use.

• Low RNA content in cells or tissues used.

  Different tissues and cells have different RNA contents, and thus the expected yield of RNA will vary greatly from these different sources. Please check literature to determine the expected RNA content of your starting material.

Clogging can result from one or a combination of the following factors:

• Insufficient solubilization of cells or tissues.

  Ensure that the appropriate amount of lysis buffer was used for the amount of cells or tissue.

• Maximum number of cells or amount of tissue exceeds kit specifications.

  The optimal input of plant tissue or filamentous fungi has been provided for each kit under Kit specifications, and also in the product insert.

• Too much cell debris in the lysate supernatant.

  Ensure that most cell debris is removed in Step 1c in the protocol.

• Insufficient Vacuum.

  When using a high-throughput kit with a vacuum manifold, ensure that a vacuum pressure of at least -650 mbar or -25 in Hg is developed.

• Centrifuge temperature is too low.

  Ensure that the centrifuge remains at room temperature throughout the procedure. Temperatures below 20°C may cause precipitates to form that can cause the columns/wells to clog.

If the RNA does not perform well in downstream applications, it may be due to one or more of the following:

• RNA was not washed 3 times with the provided Wash Solution A.

  Traces of salt from the binding step may remain in the sample if the well is not washed 3 times with Wash Solution A. Salt may interfere with downstream applications, and thus must be washed from the well.

• Ethanol carryover.

  Ensure that the dry spin under Column Wash in the centrifugation protocol or the extended vacuum in the vacuum protocol is performed in order to remove traces of ethanol prior to elution. Ethanol is known to interfere with many downstream applications.

These kits can process multiple plant tissues including but not limited to the following:

• Leaves (young and mature)
• Stem
• Roots
• Mature Seeds
• Developing seeds
• Needles
• Zygotic Embryos
• Flower buds
• Root / Shoot phloem
• Pollen
• Bark

Yes, these kits are capable of purifying dsRNA as well.

Yes, this kit is able to process freeze-dried leaves.